Hi Tom,
I appreciate you taking the time to respond. I could re-install the games, but that would mean re-downloading 100s of gigabytes from Steam servers unnecessarily since the games run from the steam client as is without issue. They were on a non-OS drive and when you add the location back to steam, it recognizes them immediately. The games then work but it doesn't re-populate the registry with the keys necessary for the games to show up in the program list. I have been adding the keys manually, and for the most part, that seems to have worked in adding the game to the GameEx menu. However, for some reason, I hit my first game where it didn't. It takes me considerably less time to populate the information then re-downloading 50gb games. So, because it didn't work, I figured that maybe gameex was looking somewhere else for installed steam games.
This is where I assumed that GameEx was looking:
Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Steam App {appid}