I figured out my HL2DM problem! The problem is that most of the servers didn't automatically get the update, so they were in an outdated version of the game. All I had to do was restart my server. I knew it worked when it took like a minute to restart when it usually takes like 15 seconds. So now I am happy.
On a sort of related topic, I am almost done with my new HL2DM map! It will have custom models and some cool unique effects!