The only problem with this is - where and when are you ever going to play Camargo?
AA's stated plan is to turn Johan into the Braves' version of Marwin. If he's only going to play when Ozzie, Dansby, and Donaldson get a breather, he's simply not going to get enough ABs to be as effective as he can be. If they're not going to play him on the grass too so that he'll get 400-450 ABs, you might as well trade him while his value is high. I'm not particularly interested in trading him either, but if you're not going to find some way to get him into the lineup at least 4-5 days a week use him to get you a full-time player.
Call Cashman and offer Johan for Frazier straight-up. Bet he takes it. If you want Gray too, offer him Camargo and Wilson for both of them. Then go sign Gonzalez to replace him and you haven't lost anything while getting the SP "upgrade", the full-time LF, and have still upgraded the bench (just with Gonzalez rather than Camargo). That would still leave you with Riley and all the other arms if AA still wants Realmuto.
I agree we need to upgrade the bench, but not at the expense of having a Markakis/Duvall platoon on a corner.