A port, maybe, but considering the parties involved have no love for each other (SK, Konami, Nintendo), I doubt it will happen.
It would make much more sense to port over number 2, or even 3, and I think there's more evidence for that: I was surprised to see that SSB:B will include Metal Gear Ray and "another, newer" Metal Gear? What? Nintendo normally doesn't advertise other people's software that easily, especially since MGS3 came out very recently comparatively.
The voice acting thing means nothing. David Hayter says he went into Nintendo to do the voices for SSB:B, end of story. Considering that he is DONE with that voice acting session, there is no evidence that anything he did would be used for a new game, or that he would be coming back.
Twin Snakes was a total failure on the Cube (due to many reasons, most of them outside of the game itself). Porting a hugely successful game like RE4 makes sense from a publisher's standpoint; porting a terribly unsuccessful remake of a great game like Twin Snakes makes sense from a consumer's standpoint only. MGS2 or 3 I think are much more likely, but even then chances are slim. I retain hope though! Waggle + MGS = win.