I need the client to be able to send messages/signals to the server along with arguments, basically the same as remote events. But I need a way of doing this without using remote events, it is for an anti-cheat. Firing remotes is vulnerable to exploits that pick up the signal and arguments passed by. Using a different method other than firing remotes would be more secure since these types of exploits only pickup remote events. Any ideas?
So there are ways to do this with instances that replicate to the client (e.g. character item deletion) but this is not really recommended. There is no point in using remotes with your anticheat however because it's a complete waste of time and as you said above opens up connections that can be intercepted and blocked.
Logging isn't worth a bypassable anticheat and you should never ban players for a client-based anticheat.