Atroma won't let him take command, Finn's pretty sure. Luckily. Although--hmm.

"Eighteen small habitation craft, one slightly larger social area, but the real prize is the Marsiva. That's the big ship - all the other ones can't move out of its range and if anyone tries to stay behind when it moves on, it teleports them back. If you could get control of the Marsiva, you'd control the whole fleet."

There. That should be a safe enough goal to get into his mind.