Fake Dedicated Servers

By no means am I amazing at Halo CE. Not trying to toot my own horn but I have a pretty decent shot. Started noticing on CE maps mostly and some in H2/H3 that whenever I would have the jump on the opponents with the pistol (in CE) after 3 supposed head shots the guy turns around and I’m now on my 4th or 5th shot and I have OS and I get shot the hell down. I had the OS on lock from using my timer so I know he didn’t have that. Not sure if the hit register is off some way or if the “dedicated servers” is slang for “player host”…because I know what that is from back in the day where people bridged host and got a crazy unfair advantage…and that’s how these matches felt like.