I question if we'll even get any value if we exercise the option and trade him in the off-season. He seems like a "motivation" guy, and his struggles can be tied to the whole "holy s%*#, playing for this team is bleak as hell right now", and his recent surge is because he's excited at the prospect of playing on a happier/better team. We saw this with Moncada - dude was killing it playing with his countrymen for Team Cuba in the World Baseball Classic, and then was a bum again weeks later when he was playing for the Sox.
I feel if we don't trade Robert now, he's going to be depressed again after having the potential "shiny new team" idea pulled out from under him and have a down second-half, leaving us with a less tradable asset at a $20M price tag.