Hey there steven8124,
We wanted to be upfront and set some expectations regarding what you described. Normally, part of troubleshooting an app not opening requires that the app be deleted, then downloaded a second time. As you already mentioned that the apps are no longer available on the App Store, there may not be a way to get them working a second time.
With the above details in mind, and while an app no longer being available in the App Store would explain the behavior you described, we'd like to help by learning more about what's happening, along with ruling out some basics:
- What occurs when you try opening the game apps that are no longer available in the App Store on your older iPad model?
- Any error messages, or error numbers showing when you try?
- Which iPad model are you using, and which iPadOS version number is installed? You can find both details under Settings > General > About.
Cheers!