The MCMG were in ROH back in February, facing the Kings of Wrestling, which ended with a DQ run-in.
It was later explained that TNA strongly requested their team not take the loss (and didn't make this clear until late on.) ROH didn't want their team to lose, so the DQ finish. ROH probably isn't up for doing it again, but who wins and loses doesn't matter as much on a random indy show.
I agree that JR and Snow would make a better team right now than JR and Lawler, but that creates the question of what to do with the King. People like him so they're going to keep him, and I doubt he's gonna wanna stick around to do Sunday Night Heat.