Playing the Oracle Engine mission, myself and two teammates in the final boss room. I died underneath an ogre and couldn't be reached by a teammate to res me, so I re-spawned myself. This placed me well outside of the boss room on the pathway you take as you ascend up to the observatory (staircase just before the point where the last shrieker spawns). When I was walking on the highest point of the pathways just past that shrieker spawn, I entered an out-of-bounds zone with the turn back message and died. I was not able to walk back to the observatory for the remainder of the fight because of this. This pathway was not out-of-bounds on the way in, so I'm pretty sure this is a bug. Luckily, my teammates stayed alive and were able to complete it, but if we had all died I think we would have all been stuck outside that room and unable to complete the mission.