Vaal core forever

https://imgur.com/yEM9aPp

I was with a friend in Trial of chaos. I picked up the vaal core, when I tried to insert the vaal core, game said I have no vaal core, my friend inserts the vaal core which he didnt picked. (?!?!?!)

We move to next room, the boss, I still have the debuff from the vaal core. While fighting the boss, an army of monsters appear around me. (?!?!?!?!?!?!?!?!?!?!)
The monsters were also marked with red icons on the minimap. My friend dies, I defeat the boss, but the game doesn't recognize that, so I fight forever in that arena with an infinite army of vaal appearing around me.