Sorry I don't have linux so don't know how to make an easy launch executable of the game for it...
On the other hand you should be able to manualy launch it in command line if you install the Ruby compiler following their doc : https://www.ruby-lang.org/en/documentation/installation/
You will also need to install the dependancy packages, I think it should just be those two (but I haven't yet verifyed on a fresh install which are needed so don't hesitate to tell me if an error arise) :
- https://github.com/piotrmurach/tty-screen
- https://www.ruby2d.com/learn/get-started/
Once everything is installed you can open a terminal in the same folder as the .exe and use the command "ruby RubyDungeon.rb" to execute it... Again I didn't test it so no guarantee it'll work on Linux but it might.