New here, been having an issue with the game I get to this point but the cutscene that is suppost to happen where I get the Chosen sewer key never shows up, I fallowed the guild to a tee, I'm running the game on the ver 1.02 patch and I can't seem to get that scene to happen. Even did all the side quests I can in hopes that might trigger it.
So far the only side quest I haven't finished is the bird one. I have the grappling hook, helgak flute, Cell keys, Core key revealed, Jinam security pass, Corite Lens, mold antidote and paint spray... along with x3 bird seed.
Any help would be greatly appreciated.

I am not sure, but if it will not work no matter what you try maybe someone here knows of a bypass, or has a saved file past that point with all the other stuff you have. I hope someone has a solution for you.

I had this same agonizing problem for awhile until I stumbled upon a boss in a new area. To get to this new area (which is closer to the core) go back to world 7 and go into the mold forest again. I took Badu along but I'm not sure it was necessary. I don't think I needed the breather masks or the earplugs this time but I had them with me. Press the tab key to reveal your map. You want to head up all the way the the topmost exit (marked in yellow) on the right side of the map. This will lead you to a new area where you have to find keys and turn switches on to get through. Lots of UnDead here so bring potions to attack them with. At any rate, when you get through all that you will end up fighting this big squidlike thing sitting on a pile of rocks. Like moonrocks or is it fungus lol. Defeat this boss and then go see Azziz on world two. Now the scene with azziz and Alisa should happen and then some robot? dude or other will give you the chosen sewer key...finally! I think this all iis in the walkthrough somewhere but for some reason I never read it. I hope this helps.

I have this issue now.

Tried above post, went there but it was excavation/mining site with robots not undeads.Which is now empty after destroying helgac crawler or whatevver that boss was.
Captured Wind City but can't progress further.

Talked with the Azziz but it feels like new dialogues cuts in the middle?

Checking various (remaining) guides in the web but nothing helps...