im not sure unfortunately, im not super familiar with linux
i used ubuntu for testing, seems to be only certain distros that have this issue?
same on Debian. game uses steam protection to run. instead of looking for a solution to link that steamAPI file you'd better ask why it happened on DRM free storefront. I just sent error report, hopefully itch support can review this game and will ensure we don't need to dance around steam DRM to run this game.