Forewarned and forearmed; Quest not finishing
event progression bugged in most personal story, living story, and dungeons, anet working on a fix, but you will have to try again later.
To go along with the progression bug there appears to be issues with walls and the NPC/monsters. I just tried this a few times (same progression bug) and the NPC with me and the monsters when fighting would go outside of the tunnels and i could no longer attack them.