How do I patch an android game I paid for, but now doesn't work because the devs shut a server off?

I paid for Puzzle Quest 2 on android like a decade+ ago. It is a local single-player game. It has a validation check when you open the app. That check fails because this game is ancient and the servers are offline.

I want to replay the game I paid for. I have the APK from an APK site. It's even been pulled from steam to push their crappy p2w pq3. Anyone have tricks to crank an APK and bypass a server check? I've decompiled the APK but am in a bit over my head.