Unkillable Skeleton

Bug Report ID: #2,355,847,057
the skeleton has no health bar can not be killed with any abilities. Had a friend come in with RF to see if it just couldnt be targeted but he does not appear to take dmg. There are also whisps around the strongbox that do not have healthbars and are attacked when i use my heavy strike. Need the skeleton dead for valdos map completion

I am still in the map if anyone has ideas for things i can try