There is if it's never mentioned or alluded to within the original franchise. My own personal story of how Canach actually saved the world by 80s disco dancing isn't suddenly canon because it happened in an alternate universe...

Congratulations. There has ever been a version of Tyria in which that happened. Making up the tale only made you aware of it. It's Myst ages rules. You didn't come up with it. It was always there. Making up the tale only made you aware of it.