Ah ok, yeah might work to shit on the patreon rulesThe game isn't on Patreon... strictly speaking.
The game is on the dev's website that you can access if you're a patron. As far as Patreon is concerned the dev makes wallpapers lol.
I know little to nothing but most copyright issues arise when you're trying to sell the game. Since that's not happening it's more similar to making a youtube video with cover songs, and that's generally allowed.
Well for the music... in my country we have "gema" a organisation looking up comypright issues, and is especially active for youtube... so many lets plays and other things are gone because of that. Its not that carefree to just use any cover songs and make short videos with them as it seems... well, but i guess like this the game wouldnt cause that much attraction in this direction anyways.
Well, on the other side i hope the DEv can get enough attraction to make a coin out of it, so its worth the development time and we can get more and bigger updates