Seeing as how they are basing their work on a leaked (stolen) version of the TF2 source code from Valve, I don't see this project even existing for very long, much less contributing anything back to Valve.

There actually is https://www.eurogamer.net/articles/2011-02-21-the-boy-who-st... Dude got 2 years probation, Nowadays he steals source code for the Chinese I guess (tencent).