(Really wish there was a spoiler tag here as it is a big fugly with such long lists of code)

// Log of Currently Installed WeiDU Mods
// The top of the file is the 'oldest' mod
// ~TP2_File~ #language_number #component_number // [Subcomponent Name -> ] Component Name [ : Version]
~BG2FIXPACK/SETUP-BG2FIXPACK.TP2~ #0 #0 // BG2 Fixpack - Core Fixes: v10
~BG2FIXPACK/SETUP-BG2FIXPACK.TP2~ #0 #1000 // BG2 Fixpack - Game Text Update -> GTU Light (by Wisp): v10
~BG2FIXPACK/SETUP-BG2FIXPACK.TP2~ #0 #100 // Party Gets XP for Sending Keldorn to Reconcile With Maria: v10
~SETUP-BGT.TP2~ #0 #0 // Baldur's Gate Trilogy - Core: 1.18 (28 Apr 13)
~BG1UB/SETUP-BG1UB.TP2~ #0 #0 // Ice Island Level Two Restoration: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #1 // The Mysterious Vial: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #2 // Additional Elminster Encounter: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #3 // Angelo Notices Shar-teel: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #4 // Finishable Kagain Caravan Quest: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #5 // Coran and the Wyverns: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #6 // Kivan and Tazok: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #7 // Branwen and Tranzig: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #8 // Safana the Flirt: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #9 // Appropriate Albert and Rufie Reward: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #10 // Place Entar Silvershield in His Home: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #11 // Scar and the Sashenstar's Daughter: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #12 // Quoningar, the Cleric: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #13 // Shilo Chen and the Ogre-Magi: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #14 // Edie, the Merchant League Applicant: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #15 // Flaming Fist Mercenary Reinforcements: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #16 // Creature Corrections: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #17 // Creature Restorations: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #18 // Creature Name Restorations: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #19 // Minor Dialogue Restorations: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #20 // Audio Restorations: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #21 // Store, Tavern and Inn Fixes and Restorations: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #22 // Item Corrections and Restorations: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #24 // Permanent Corpses: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #27 // Sarevok's Diary Corrections: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #28 // Prism and the Emeralds Tweak: v13.1
~BG1UB/SETUP-BG1UB.TP2~ #0 #29 // Duke Eltan in the Harbor Master's Building: v13.1
~UB/SETUP-UB.TP2~ #0 #0 // The Kidnapping of Boo by Cliffette: v26beta2
~UB/SETUP-UB.TP2~ #0 #1 // The Suna Seni/Valygar Relationship: v26beta2
~UB/SETUP-UB.TP2~ #0 #2 // Kalah and What He Was Promised: v26beta2
~UB/SETUP-UB.TP2~ #0 #4 // Gorje Hilldark and the Extended Illithium Quest: v26beta2
~UB/SETUP-UB.TP2~ #0 #5 // The Pai'Na/Spider's Bane Quest: v26beta2
~UB/SETUP-UB.TP2~ #0 #6 // Restored Crooked Crane Inn: v26beta2
~UB/SETUP-UB.TP2~ #0 #7 // Restored Encounters: v26beta2
~UB/SETUP-UB.TP2~ #0 #8 // Artemis Entreri in Bodhi's Lair: v26beta2
~UB/SETUP-UB.TP2~ #0 #9 // Corrected "Xzar's Creations": v26beta2
~UB/SETUP-UB.TP2~ #0 #10 // Restored Hell Minions, by SimDing0: v26beta2
~UB/SETUP-UB.TP2~ #0 #12 // Item Restorations: v26beta2
~UB/SETUP-UB.TP2~ #0 #13 // Yoshimo's Original Portrait: v26beta2
~UB/SETUP-UB.TP2~ #0 #14 // Anomen's Original Portrait: v26beta2
~UB/SETUP-UB.TP2~ #0 #15 // NPC Portrait Restorations: v26beta2
~UB/SETUP-UB.TP2~ #0 #16 // Corrected BAMs and Scripts: v26beta2
~UB/SETUP-UB.TP2~ #0 #17 // Corrected Character Names and Biographies: v26beta2
~UB/SETUP-UB.TP2~ #0 #18 // Restored Minor Dialogs: v26beta2
~UB/SETUP-UB.TP2~ #0 #19 // Restored Bhaalspawn Powers, by David Gaider: v26beta2
~UB/SETUP-UB.TP2~ #0 #20 // Extended ToB Item Descriptions: v26beta2
~UB/SETUP-UB.TP2~ #0 #21 // Throne of Bhaal Minor Restorations: v26beta2
~UB/SETUP-UB.TP2~ #0 #24 // Sarevok's Remorse: v26beta2
~UB/SETUP-UB.TP2~ #0 #25 // The Murder of Acton Balthis, by Kulyok: v26beta2
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #40 // Change Viconia's Skin Color to Dark Blue: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #60 // Weapon Animation Tweaks: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #100 // Commoners Use Drab Colors: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #110 // Icon Improvements: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #130 // Force All Dialogue to Pause Game: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #1020 // Alter HP Triggers for NPC Wounded Dialogues: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #1080 // Add Bags of Holding: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #1120 // Stores Sell Higher Stacks of Items: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #1130 // Reputation Resets in BG2 (BGT Only): v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #1170 // Bonus Merchants (Baldurdash): v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #2040 // Universal Clubs: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #2090 // Change Experience Point Cap -> Remove Experience Cap: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #2210 // True Grandmastery (Baldurdash): v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #2220 // Change Magically Created Weapons to Zero Weight: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3000 // Higher HP on Level Up -> Maximum: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3012 // Maximum HP for NPCs (the bigg) -> For Party-Joinable NPCs Only: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3030 // Easy Spell Learning -> 100% Learn Spells: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3040 // Make Bags of Holding Bottomless: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3060 // Remove "You Must Gather Your Party..." Sound (Weimer): v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3080 // Unlimited Ammo Stacking: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3090 // Unlimited Gem and Jewelry Stacking: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3100 // Unlimited Potion Stacking: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3110 // Unlimited Scroll Stacking: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3121 // Happy Patch (Party NPCs do not complain about reputation) -> NPCs Can Be Angry About Reputation but Never Leave (Salk): v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3125 // Neutral Characters Make Happy Comments at Mid-Range Reputation: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3150 // Turn Off The Hideous Cloak-of-Mirroring, Spell-Trap, and Physical Mirror Animations: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #3200 // Sellable Items (Icelus): v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #4000 // Adjust Evil joinable NPC reaction rolls: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #4031 // Consistent Stats: Edwin -> Use BG2 Values: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #4041 // Consistent Stats: Jaheira -> Use BG2 Values: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #4050 // Change Jaheira to Neutral Good: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #4061 // Consistent Stats: Minsc -> Use BG2 Values: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #4071 // Consistent Stats: Viconia -> Use BG2 Values: v16
~BG2_TWEAKS/SETUP-BG2_TWEAKS.TP2~ #0 #4100 // Change Korgan to Neutral Evil: v16
~SETUP-BP-BGT-WORLDMAP.TP2~ #0 #0 // Worldmap for Baldur's Gate - including colored Baldur's Gate map icons: v10.2, beta 3
~SETUP-BP-BGT-WORLDMAP.TP2~ #0 #1 // Worldmap for Throne of Bhaal -> Use new Worldmap for Throne of Bhaal as well: v10.2, beta 3
~WIDESCREEN/WIDESCREEN.TP2~ #0 #0 // Widescreen Mod -> for the original Infinity Engine (CHOOSE THIS!): Widescreen Mod v3.07
~SETUP-BGTMUSIC.TP2~ #0 #0 // Baldur's Gate Trilogy - Music -> Full Baldur's Gate and Tales of the Sword Coast Music
~BG1NPC/BG1NPC.TP2~ #0 #0 // The BG1 NPC Project: Required Modifications: v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #1 // The BG1 NPC Project: Banters, Quests, and Interjections: v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #8 // The BG1 NPC Project: Add Non-Joinable NPC portraits to quests and dialogues: v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #9 // The BG1 NPC Project: Ajantis Romance Core (teen content): v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #10 // The BG1 NPC Project: Branwen's Romance Core (teen content): v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #11 // The BG1 NPC Project: Coran's Romance Core (adult content): v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #12 // The BG1 NPC Project: Dynaheir's Romance Core (teen content): v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #13 // The BG1 NPC Project: Shar-Teel Relationship Core (adult content): v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #14 // The BG1 NPC Project: Xan's Romance Core (teen content): v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #28 // The BG1 NPC Project: Bardic Reputation Adjustment: v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #2 // The BG1 NPC Project: Give Edwin his BG2 portrait: v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #3 // The BG1 NPC Project: Give Imoen her BG2 portrait: v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #4 // The BG1 NPC Project: Give Jaheira her BG2 portrait: v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #5 // The BG1 NPC Project: Give Minsc his BG2 portrait: v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #6 // The BG1 NPC Project: Give Viconia her BG2 portrait: v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #17 // The BG1 NPC Project: Alora's Starting Location -> Alora Starts in the Hall of Wonders: v22_20150614
~BG1NPC/BG1NPC.TP2~ #0 #31 // The BG1 NPC Project: Sarevok's Diary Adjustments -> SixofSpades Extended Sarevok's Diary: v22_20150614
~SETUP-AXETEST.TP2~ #0 #0 // Pangaea's Firefroster Mod

Well you have the latest (BGT compatible) versions, and they're installed in the correct order, so curiosity sated. Looks like it very well could be a UB restoration issue.

BG- Unfinished Business restores the Ice-Island level 2 (where Dezkiel would show up).
It works fine on my system but I've got older versions of both that and BGT installed.

(Though Ice-Island level 2 isn't really worth it IMO - not a very interesting level and just makes it a longer stroll to the boss fight.)

Odd that it doesn't work now, or on my system at least. Some of the material was dropped for valid reasons though. I found the minimap of the area, and like you say, it doesn't look very interesting.

As a little aside, I had a strange timing experience with Kiralee (the succubus) in Durlag's Tower. The PC fired a magic missile, then got dire charmed, and then the magic missile salvo killed her. We didn't get any XP for it, presumably because the moment she was killed, the person with the killing blow was not technically in our party, being hostile.