WWE didn't let Perry Saturn do the DVD, and he'd been doing it for years. No way they let Kane, much taller and more powerful, do a DVD, especially when he doesn't have much (if any) experience doing it before.
My problem with the Brainbuster is that it's been typically a Junior move ever since Jushin Lyger made it one of his signature moves.
BTW, I blatantly stole Owendriver '97 from Matt Nute at 411, he does a column on finishers, very cool. (This week's is Ki-Krusher). You can get it
here.