While this is classic Valve non-communication, apparently the devs were hacking or reverse-engineering some closed source stuff, that Valve might not have agreed with.
https://x.com/csco_dev/status/1533103185543548929
Just so we are clear on how the mod works on our side, there is no leaked code involved. We're using a build from 2020 that has security exploits and a hacked dedicated server to be able to even play online while working on it internally.
The mod cannot be released in this state
This is all just some third-party information, I have no idea about this and don't really care about Counter-Strike.