I figured it out!

I had to add the following into the server properties file + restart the server

enable-command-block=true

The problem was that command blocks just... didn't work I guess, and the pressure plates relied on them. Adding that small command to the properties allowed the plates to start working again.

Answered!

I had to add the following into the server properties file + restart the server

enable-command-block=true

The problem was that command blocks just... didn't work I guess, and the pressure plates relied on them. Adding that small command to the properties allowed the plates to start working again.