Save Files Not Recognized

My save files will not load after a forced shutdown (my computer locked up and windows hung). Now I am faced with a complete restart of game with all progress absent. When copying the backup .sav file back over to the current save folder, it's not recognized and 'load game' is grayed out. I've tried making sure that the Windows Firewall settings allow Dead Space on both Private and Public networks, to no avail. The autosaves also will not load and the game fails to load them if I attempt to overwrite the other autosaves with the ones that contain my progress. I have tried re-syncing to the Steam Cloud, and that doesn't work either.

I was on Chapter 10, on NG+ Hard, with a fully upgraded suit, Plasma Cutter, Pulse Rifle, Ripper, Contact Beam and Line Gun. The Flamethrower was mostly upgraded and the Force Gun was halfway upgraded. I've sank about 40 hours into the game and it's really upsetting to have all of this progress inaccessible.

I've tried copying the backed-up saves and renaming them, too, per this video https://www.youtube.com/watch?v=zSSKFHvmNf0 and it didn't work either. It just fails to load.