Okay! So I found a few things. I'm sorry these aren't more precise--I can't recreate the problem so I can't test it myself.
My research implies that this issue MIGHT be related to Mac permissions--operating systems often don't running unidentified files. So you may be able to avoid it by downloading the https://itch.io/app and running it through that.
Another possible fix:
"I found that you can also left click on the game, select show package contents, go to contents folder>MacOS and left click open the terminal"
If that doesn't work, email me at beautiful.lightness@gmail.com and I will give you a secret way of solving this problem.