Invulnerable monster in ultimatum blocking soul core placement socket

Two part bug report:

1. Some monster remain "undead" when killed, staying like statues and blocking space.

2. Such monster body blocked the socket for vaal soul core in ultimatum, making it impossible to continue.

The character attempts to reach the socket to place it, but on collision with the corpse it stops, while taking endless degeneration damage from the soul core.