Can't sync games between my Deck and PC

[Socrates Jackson]

But only some games (Dead Estate and Inscryption, specifically).
I often take the Deck when I travel and play games on it. Usually, they update into the cloud fine, but these two in particular just won't. They'll say they uploaded, but when I start on a different system. they'll have the warning that there's a sync error and ask which file I want to use. It doesn't matter which one I pick, it always defaults to the local one. Achievements transfer, but the saves won't.

Has anyone else seen this? Is there a fix? Is this a Steam problem, or something with the games themselves?