I don't think there's enough information contained within the sticker to actually extract, even with chemical testing. It's unlikely Sega used any kind of special printing techniques that can't be reproduced by the average person. It's a silly UPC sticker. What company is going to invest anything more than necessary for something like that? The only alternative is trying to establish whether the sticker is 20 years old or not. But the thing about dating is that it's inexact. Even carbon dating, what they use to determine the ages of shit like fossils, leaves open a gigantic range of time.
If people have successfully snuck forged baseball cards through professional graders (it has happened) then what the hell do you expect is going to happen with a UPC code printed on a sticker paper that is more than likely easily found today?
You've been told before that you're overestimating what can be done and I'll echo that now. You're overestimating it by a longshot. Show a professional a pristine Sonic with an authentic pristine sticker and a pristine Sonic with a forged sticker and I'd say that professional will fare no better than chance, CSI bullshit or otherwise.
I'd be willing to participate in this experiment but then we'll all be accused of forging stickers and showing the world how to do it. No real way to test this without causing a shitstorm.