Please delete the trainer, custom keys, debug folder where the trainer resides and all files in
Learn how to make your own Trainer Cleaner for the above paths here.
Reboot PC to clear excess memory, get a fresh copy of latest trainer and extract it. Run trainer as admin, read the instructions and try again. At times, a new game may be needed to resolve failed options if the data in your save file was altered. Use on a new game and test the option. If it now works, quit to main menu and load your save and try it again. May also need to run the game without the trainer first and play a bit so the save file gets updated to use possible new values. This typically will resolve the issue.
Re-verify your game files in Steam, and try on a new game, not a save.
It wasn't the game files, they verified on both PCs I tried on, but it seems to be the save, even though I hadn't loaded it yet and was trying to load from the main menu, it still apparently saw the old save and was causing issues... once I tried to activate the trainer AFTER I started a new game, it worked just fine. Thank you for your guidance.🙂