Forum moderators can't do shit. Especially because smurfing is 100% legit and "boosting"? Boosting is when you pay a (professional) player to get on your account to boost your ranking from silver 2 to Plat1 or w/e
Boosting is legal in China, it is not acceptable in the US and Canada but they don't really do anything unless you get thousands of reports for it.
i bet that guy is bluffing. and even if he isn't, ull be totally fine