Yep, it was predictable, but then again, everyone had to know the ship wasn't going to get destroyed...that was obvious.
I don't like the Chloe character either. Same reason. As for whether or not Rush knew - it doesn't matter. Personally, I don't think he knew. I think he might have guessed at it, yes, but no point in risking everyone's life on a hunch when he knew the Col. would likely never believe him anyway. Better to risk losing 15 and be right (about your hunch) than to convince the Col. about your hunch, keep everyone aboard and (*oops!*) your wrong! *poof*