Ultimatum boss bugged

The trial master is not working, after he uses the second skill he freezes time and walk in my direction till dead.

Full description and testing:
I did the first to get points. I noticed and it feels weird

I did 2 more after resetting the game still happening.

did not think it would help but verified game files and proceed to testing

I did once each type of trial, Happened in the tornado bird, and in the necromancer bird.
I don't know if it persists with the Chimera the door refused to open after i killed last boss