How do I report someone for stealing a gamemode and then trying to copyright it?

I have recently come across a steam user that has stole DarkRP, renamed it and is now going to copyright it. I respect the owners of DarkRP and I suspect they don’t want people to steal their gamemode

Here is his steam profile:

He has it private because he thinks no one can find him then

and the name of his gamemode is:
Doctor Who RP

and he has said he made it, but when looking into it, Its a port over of DarkRP with the name changed.

he isn’t copyrighting anything

don’t worry about it

The game modes has been under an MIT license for two years.
Use that information as you will

Lol I can customize darkrp and give it a name, but my server will be at the bottom :v

FPtje has pretty much given full permission for anyone to rename/change the DarkRP gamemode to their will: