As far as I have looked, I have found 3 dead ghosts in the Seraphim Vault. The first one (Hive 3) is the one that we already know of from glitching the map. It is on the other side of the hallway when you first encounter the hive in the vault. It is behind a box The second one is above Rasputin's cortex (I think), it is that giant thing in the center of the room you fight the Ogre. You must maneuver to reach the top. The third one is below Rasputin's controls (the ones you have to approach in the second mission of the DLC). It is in one of the walls inside. This last two give you the grimoire entries for Rasputin 2 and 3 As far as I know, I'm still missing one dead Ghost that gives me Rasputin 1. Has anyone found it yet? Maybe in the new areas the dlc opened.