Singing caverns - Diamora, Song of Death

Im stuck in the boss Room for Diamora, Song of Death.
Boss spawned, did 1 spell, dissapeared and now my character is locked in the room.

I Can't log out to reset the room
I can't Respawn at checkpoint.
Boss fight is completely bugged.
There is no interactables (not that i know if there is any)
Just the bosses annoying constant singing.
Tried logging into a different character, restarting the game and so on.

I am the same!

I merc bombard mortared her then she disappeared.