"A major UFC name" could be a guy no longer with the company.
Of the active UFC roster:
I know Josh Barnett did some pro wrestling in Japan while in Pride; has the charisma/size
Alistair Overeem- probably does't have the personality, but has the prototypical Vince physique. Maybe he is tired of getting KO'd.
jeez idk. unless its some no name, which could be.
former guys that could make sense: Chuck Liddell, Randy Couture, ect. would have said rampage but no way WWE touches him after he got TNA stank on himself.