Proof? Atleast the Seal War would have happened in the correct timeline...
Here's some proof the people on Outset island mention the hero,but the sages are never talked about it's the hero who gets all the credit.
Yet in ALTTP the people seem to know about the Sages,and the role that they played in the Seal War.
So the point is that the Sages played too big of a role in the War to not go down in history alongside the hero.