His "extensive" research is obviously to lure in the idiots. That's not a proto and everyone knows it. It's just a standard cart, though different art on the front. PAL region I guess, though he says NTSC. Maybe it's an Asian version?
Definitely not beta or proto of any sort though. He even says he doesn't notice any differences in game, but of course writes "but there could be.." just to get people to wonder. Worthless :(