My Epic Games Launcher won't open on my Mac

It doesn’t give me any details.

I’m experiencing the same thing. No details or anything, it looks like it’s going to open and then nothing happens and the icon disappears from the app bar.

Just resolved this issue. I’m running on a Hackintosh (PC with Mac OS installed on a separate hard drive). I’m assuming you’re also using a non-Apple machine. What I had to do was install the Nvidia web drivers and make the necessary changes in Clover Configurator. See this link for details:
How to properly Install Nvidia Drivers on High Sierra