I'd be pretty surprised if Rojas gets dealt. and certainly wouldn't expect is. to be someone that the team will go to market actively shopping.
He's further away from MLB, but that's likely more feature than bug at this point. His ETA if things continue to progress well is more or less right as Nico hits free agency. He's also a year and a half from needing to be added to the 40 man roster.
I'd suspect that Caissie and Alcantara are indeed the top trade chips that get bandied about the next six weeks. I also wouldn't be surprised if some starting pitching gets sent out the door. None of the immediate MLB depth obviously, but potentially some of the next wave guys like Sanders. Maybe Wicks, despite being more ready, just because of how far down the depth chart he is?