Locate the bodies of Vance and Barnes.Locate means you got to loot off their bodies. You’ll find Vance in Level 1 - Subversion, when you pass your first power node and into the Gyro Ring Room. You'll find Barnes in Level 4 - Vengeance, shortly after opening a door via a Key-Card, where your current objective will be listed as "Follow the waypoints to the Research Deck". Barnes will be lying next to a Log.
Loot both bodies, and the trophy will unlock as soon as you looted Barnes corpse. Poor fellas