Maybe it's reading too much into the excitement of an emotional night, but it sounded more and more last night like Bryce is going to resign and stay in DC. If Rizzo feels the same, he has to be more inclined to include Robles in a deadline deal to make a big splash. Now, he wouldn't trade Robles for strictly a rental. It would have to be a piece to help this year and in the future, or at least a rental combined with a long-term piece.
Of course, ideally you'd trade Eaton or Soto because Robles is the guy who can play CF out of the "Big 4" OFs in the system. You'd obviously be selling low on Eaton at this point, something you don't want to do. Soto could be a perennial All Star for 15 years, so it's also not exactly ideal to trade him.
I think unless a great deal is available that includes both immediate help this year and long-term help, Robles remains a Nat. In an ideal world, Robles gets rolling and comes up to impact in September, Eaton stays healthy and gets rolling, and Bryce resigns. Then in the offseason you can try and trade Eaton and go with Soto in LF, Robles in CF, and Harper in RF. Or just keep Eaton knowing injuries will strike at times.