Abomination Shavronne and The Depraved Trinity bug

Somehow while I was fighting Shavronne in Abomination, The Depraved Trinity spawned. Futhermore when I killed the trinity, Shavronne suddenly died and her spectre linger. I couldn't complete this map to get the fragment because her spectre is still lingering and refuse to go away while the trinity had been defeated.

https://imgur.com/a/CPOGqgA