coincidentally I did this one a few days ago. I didn't run into the hall problem, but just the one thing that makes most of the healer quests frustrating - you're supposed to be watching 2-3 npcs, and they are not in your party. Things like protect don't work. and in this case, you had a HUGE monster and a tiny tank. I was glad to see some better AI out of the NPCs, but in the cases their lives will fail the duty, you need a proper party formed so you can see what is going on. Not to mention that would make these quests a much better training scenario for real duties.