Hold up, You do realize with every number in existence there isnt a Largest or Smallest Number at all? Infinity is a Term not a number it has no Start and no End zero is nothing to it (All in all its more of Who shoots first)
Infinite doesn't have a beginning or end. Once tusk is activated, it can only be stopped if johnny uses his stand in the opposite direction.
The winner is decided by who goes first. GER can prevent Johnny from activating his ability but he can NOT reverse it back to 0 since there is no 0 in infinite.
Infinity does, in fact, have a beginning. The definition of infinity is something that does not have an ending, yet does have a beginning. It can thus be returned back to its original state, meaning GER wins.