[2022] Achievements were working, now not.

I don't know what could cause this to you either. Does that save show as achivements being gettable still?  

Having checked I see this game tells you if a save is Ironman, but not specifically if it is achievement-worthy or not, unfortunately.

I know nothing about the content of save game files, I'm sorry. User Mods may be able to help with that. What I can say is that if you rename them to end in .zip you can then unzip them to get the plain text files that make them up.