Boarding party last boss bugs if you don't kill the middle guy last and you most likely won't receive chest then.
My group killed the middle guy last and the chest was locked, which was a lil frustrating, since we were all eager for the biometric crafting material as well as the loot.
we've since done this encounter with a variety of ways of killing (altho we never kill the left guy last). Never once has the chest been lootable (granted, only 3 kills so far)
edit: forgot to put point of killing differant ways