The online aspects of this game were probably managed by Steam's API since it is a Steam release for the PC. This generally means it's tied to using Steam's API within steam_api.dll. There are tons of emulations for this that can fully emulate all aspects of Steam (match making, DLC access, online/offline modes, etc.) which you can find on sites like cs.rin.ru.
The market for modding/cheating/botting is not really in the same realm as cracking/piracy/leaking of the actual property.
Publishers and developers have to make the decision to go after modders/cheaters if they feel there is a suitable case against them. Generally this involves having to prove damages or other hard-to-prove things such as infringement or similar. There is a reason this is rarely something that happens to the cheating/modding scene because it is hard to prove. There's only been a small handful of cases that ever even make it to court, and even smaller where things were won in favor against the cheater. There is no law or enforcement by the governments in the world that protect this kind of thing either.
It is solely up to the developer/publishers to protect their intellectual property and seek legal action if they feel its being damaged or infringed upon.