You can look into scrcpy, that allows you to stream mobile screen to PC. I am using this with a "burner" phone. So the game is running 24/7 and when I want to do something I can just control it via PC. If you are concert about the scrcpy project, it has Apache 2.0 License. Source code is public. So feel free to read.
Second option: If you have time to spare and are tech savvy you can create your own BlueStack. Depending on your OS (Windows/Linux), performance may vary. On windows you just can not virtualize ARM based OSs with good performance. So you would have to use Android x86 and I do not know, if the OS can run the game, but as I wrote, if you have time to spare you could give it a try.
I was trying to figure this out too. From what I can tell, it's a problem with the Google Play Games app, not Days Bygone. The reviews section has a ton of people with the same kind of issue about not being able to sign into certain games.
https://play.google.com/store/apps/details?id=com.google.android.apps.paidtasks&hl=en_US https://apps.apple.com/us/app/google-opinion-rewards/id1227019728. You fill out surveys that google sends you and you make money off them that you can use in the AppStore. My total since I started two years ago is about $20
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