well is it possible that when my saves were wiped and i started a new game forgetting i had my backup saves and then trying to import them when i remembered, maybe made them think that it was modified?
No, doesn't matter when or on what version or platform/device the saves were made, if they weren't modified, they wouldn't give that error.
The state of the game doesn't affect the saves until they're actually loaded, so starting a new game, or even deleting it, doesn't affect the save's content.