3 separate times trying to complete the Grand Washington Hotel mission on "Challenging" and the near the very end, the last NPC is stuck in the room under the escalator. We have tried offing ourselves and spawning back in. We've tried the Chem launcher, fire turret, seeker mines etc. There is nothing we can do to "kill" the NPC, we've tried not to kill all the NPC bad guys quickly as to not allow him to get stuck. Nothing has worked. I am not able to attach the image of the NPC stuck in the room.
Please advice - we are trying to complete projects.