I noticed on the itch website you can get the linux version but it says it isn't available in the app. Could you resolve this?
There's indeed a Linux version (a .tar.gz file that should be compatible with the app according to itch.io documentation).
I don't use the app myself, nor Linux, so I didn't know about that but I'll try to take a look. It won't be right now, though, since I haven't access to any Linux machine atm, sorry...
The issue should be resolved now, and the game should be available for Linux in the client.