Reproductively compatible beings with whom Adam’s offspring eventually interbreed.
Yes, that is a distinction between the RTB and a GA.
The RTB position seems self-contradictory, especially because they think Adam and Eve were specially created. If God had done that, there is every reason to believe he could have created them in such a way that they could not interbreed with Denisovans and Neanderthals. He did not. Why not? There is no really good reason for that, and it is going to come again soon elsewhere: A Science Fiction Riddle. The fact that the can interbreed (and the barriers to interbreeding are debatable regardless) seems like de facto evidence that God wanted them to interbreed. That leads to some deep incoherence in the RTB position.
@vjtorley somewhat avoids this problem by saying Adam and Eve were not specially created. So it is a hang over from common descent that allows them to interbreed. Still God could have made them infertile, but He didn’t. Why not? I’m not sure there is a good reason.
GA just goes the other direction, making a natural theology argument that if they can interbreed, then God originally intended it. That seems to be the most coherent theological position, at least to me.
Notice, all cases include interbreeding. In all cases, there are people outside the garden. We are just theologically thinking about it in different ways. And, I would add, GA is doing it head on, but RTB is treating it like a footnote. The fact that they don’t announce interbreeding up front does not some how reduce the significance of the fact that they include it in their model.