From Shion's room, go east and enter the south lab to speak with Allen. Shion needs drugs. Allen gives Shion drugs. Shion takes drugs, then goes back to her room to get some sleep (It's apparently the only room in this section of the ship, lucky Shion). After Shion has her strange "dream", go back to the lab for more cutscenes. After that, head for the elevator on the west side of this area. The one saving grace that allows this mission of Shion's to be successful is that the Realian who is supposed to be standing guard at the elevator is asleep standing up. Maybe Nephilim did that to him so we can fulfill destiny and all that.