I too defeated her in the tea house. Some details in case it matters: I avoided the immediate-post-dialogue fight so that I could position my party around her in an optimal fashion (high ground) and then attack her off guard. Summoned a cloud of daggers and then did everything I could to prevent her from moving: Bane, Command Stop, T's Laughter, entangle, etc... She did eventually say something and removed the fireplace illusion and didn't move as others have described. I assumed she wasn't moving because of the other spell effects holding her in place. Or maybe her pathing AI wouldn't allow her to walk further into the cloud of daggers (which likely was between her and the fireplace).
I remember thinking when she went down that the game shouldn't actually allow us to win that fight. I was going to suggest it in the feedback. IE: Maybe that version of her should just be a Simulacrum or Illusion. Or maybe she should just go invulnerable and teleport out when the moment occurs that would normally kill her. But it sounds like it was more than just a lucky win. Definitely seems there is something buggy about the encounter now.
