Lol, Anti. At any rate...
Allow me to explain, MoN. I think that he's trying to say that Roxas, after leaving the Organization, had fake parents in the fake Twilight Town. That would cover part of the overall scheme set by DiZ when he placed Roxas in the fake Twilight Town with a different attitude and memory in order to use Sora.
As for if he means before Roxas was discovered by the Organization, then Roxas would never have had a chance to have any adoption parents. If it's to my understanding, I believe Xemnas found him before he came to the real Twilight Town.
After all, then wouldn't someone in the real Twilight Town be able to remember Roxas, such as Heyner, Pence, and/or Olette?
If he means that when Roxas was "born", that he had had parents, no way is that possible. Not to sound heartless ( pun made yet unintended ), but he's just Sora's Nobody. He only came into existence when Sora become a heartless.
So, that wraps that up in a nutshell. Anyway, there is little proof that Aqua/Ven or Aqua/Terra can be Sora's mother and father. I rather doubt that Sora's parents will play even a minor role, if any. All parents in Kingdom Hearts is totally disregarded.
Simplest case scenario: Sora had a nameless father and mother, with no relation to any characters in Kingdom Hearts at all, thus disregarded in both name and health. And I will stab someone if they dare make a Final Fantasy pairing to explain this. Of course, it takes someone of low brainpower for that.
Most complex case scenario: Something so complexing you'd need to get every single one of the Kingdom Hearts games and piece together the pieces and bits. This one I doubt, as Kingdom Hearts lacks any sort of complexities. And if it has any, none as complex as this would be.