Factors I don't know:

What is the stamina of a gorilla? As you said, waves of humans would need to take turns. They could nurse minor wounds and catch their breath for a moment before returning to the fray.

Would the gorilla retreat from the number of foes, or fight regardless of the odds from its perspective? The 100 men may want to win, but does the gorilla see the fight as worth fighting at all?

A gorilla is strong, but how would it fare against a simple dogpile? Imagine more of a massive rugby scrum instead of a choreographed fight scene from a movie.