I’d agree that would make sense when he’s talking to Five before she starts the search. But the scene later when he appears concerned and actually looks in one of the vents throws me.

One thing that bothers me about Six being the traitor or an undercover GA agent is when Five is searching the vents to flush out a possible infiltrator. If six really is behind everything, why does he appear concerned for Five’s safety?

This is Dark Matter, you can never trust the obvious answer. Is that really Six? I don’t think so.