Most renpy games uses simple code that, most of the time, would never get broken. That's sad, I thought there was a way to like... choose the renpy version per-game, not per instance of joiplay. Have you checked long-pressing the game, going to edit and changing the "engine version"?
You can also try the apk tho, if that does not work. At least until there's a workaround.
Well some of the games explicitly required me to update the renpy version to play but conveniently enough never broke anything that ran on old code still. This is the first game that's had this issue for me. With plugins for Joiplay, you can have both say a version of renpy 7 and a version of renpy 8, but you can't have multiple versions of renpy 7 or renpy 8 since your effectively updating the plugin not adding a completely separate one. At least I think that's how that works. But I genuinely don't understand why the newer versions of Joiplay don't recognize older versions of the renpy plugin for me in the first place. I spent a couple hours trying to get it to work but reinstalling the current version of renpy 8 works fine. If someone has a way around the issue of not being able to have multiple renpy 8 versions as plugins in Joiplay and know a way to force it to recognize the older version I'm all ears, but until then I'm kinda just stuck waiting for this game to get updated to the new code.
