I'm stuck in that same room (with the Wellspring) but it happened when the fight started. NPC Lohse was up first, and she wouldn't do anything... just stuck. We re-loaded and it didn't fix it.
I'm guessing they don't have a lot of bug reporting on the end stuff yet, but I have to say that I've had bugged fights in probably every arena we did, usually related to pets being alive at the end. In this fight, Alexander is a pet to one of our players, but I think he's trying to help on the fight. So uhhhh...
