That's an interesting scene (I admit I was surprised that the male redshirt wasn't the one to die).
Rather than "random unknowing," I'd think of it as deliberate neutrality--or maybe just plain apathy for which one it'd be; I don't think Rojan thought that one or the other would have been more persuasive to remain alive. I think that as a non-human, he saw them as equals, so he thought the point of his persuasion was specifically his ability to kill--not whom he'd kill.
- Sifting TNG character quotes like no one has sifted before. Each post consists of quotes, rearranged by sentence, to produce a delight/disturbance (based on character and episode).