Canonically the actual gamble was qui-gon vs Darth maul. If qui-gon had lived, the universe would have been fine. But he lost, so it was doomed.
The force on star wars is weird, because if you’re strong enough in the force things are basically fated.
Anyway, that’s the long reason why the background music during that fight is called “The Duel of Fates”.
While that’s all a good question and thought provoking… unfortunately it’s literally just word of god that if Qui-Gon won, the light would win.
A common problem in Star Wars- the fans have put waaaay more thought and worldbuilding into it than Lucas ever did.