I'm a bit sceptical on this. Enableing such code would require a mod SDK, which we don't have (of course you can open up some files etc with a lot of time and knowledge). Let's say that you did it somehow, but since there is no mod SDK, you cannot create a mod. The other thing is, that let's say you created a mod somehow, but how did you upload this mod to a server, provided by an official provider? There are no community dedicated servers, so you cannot create a server to create such thing.
I think the video has been edited in a tricky way.