It's a little surprising that he has yet to play 2B. I mean, if Herrera's not sacrosanct... Though obviously there hasn't been any need for days off per se this week. (Unless you're a RF, I guess.)
You'd be trading Cesar for pennies, probably. Market for 2B has been weak each of the last two trade windows and would only be weaker now. Check again in late June of course.
I think your scenario is more what they are expecting. Once Franco fades onto the bench (or off the roster) there won't be any rush to trade Cesar until the off-season.