I tried to do AC explo mode with a pug, and chose the second path (ghost-eater or whatever it is called). We got to the part where we had to get Detha to the hall of the champions, but it would not update the quest:
http://img341.imageshack.us/img341/8033/gw030vi.jpg
http://img209.imageshack.us/img209/9910/gw031t.jpg
We then killed the NPC and rezzed it hoping that it would fix things. Nope.
http://img842.imageshack.us/img842/7694/gw032u.jpg
http://img831.imageshack.us/img831/8211/gw033g.jpg
We also tried going out of the room, going back in, using the other entrance etc. Quest just wont update no matter what we try.
