I tried every work-around I could find, including downloading the most recent WeiDU, running the script from the Baldur's Gate 2
folder within the GOG
...place them directly in the Baldur's Gate 2
I am having the same problem you describe having solved, but your solution is confusing.
In the failure example, you place the files in the Baldur's Gate 2 folder.
In the success example, you place the files in the same Baldur's Gate 2 folder.
I don't see how these are in any way different. I don't have a GOG/Baldur's Gate 2 folder with a complete game in it, and ANOTHER nonGOG Baldur's Gate 2 folder with the complete game in it as well.
I have one folder, called Baldur's Gate 2, where the three necessary files and folders are located when I run the .command file. Within that Baldur's Gate 2 folder, there is the game icon labelled Baldur's Gate 2, which is the executable package, not a folder.
What exactly is the difference you are describing? Do you put the fixpack items inside the Game icon called Baldur's Gate 2 itself? This would mean opening the Package.