Hey, found this other nasty bug where the son of a mother who joined a cult doesnt seem to properly leave the area making the quest impossible to turn in.
I believe this is part of the ascalon quest pack with burnger (think i butchered that one) and after killing the beholder cult and killing gall, i told him to leave in his own. He would appear at the very end and I'd tell him again to leave and he disappear only for another copy to replace the disappearing one. I tried to just talk to his mother again, but she refuses to talk to me. Making this quest unsolveable.