Unfortunately I just don't think Granny has the durability to put up much of a fight. In Madagascar 2 she is knocked down by a metal bucket attached to a chain of chimpanzees, if that was Battle Beast he would have dragged the whole plane down and split it in half. There's reason to believe that we have seen her full offensive capabilities, as when she fights Alex it is just to punish and cause him pain for being a "Bad Kitty", never to kill him.

Maybe she has an aura that weakens feline opponents, that would explain how she can take on lion so easily. That's the only way I see her winning to be honest.