For people that are experiencing this bug, I have concluded a few things that is causing it the issue.
Minions from Druids/Necros. Golem seems to be okay, but better off going no summons.
Also heard about staying inside the middle of the room as being on the outside also causes it apparently.
Posting this because they can’t seem to find the reasoning for it, though they at least acknowledged it in support.
Also only doing nightmare dungeons in WT4 today and timed events so if anyone is on Eternal or knows if we can cross party. I’d help rek him for yea. Same name in game.