I doubt you will get much information out of it.
Demos play as a fake "netconnection". Your computer is the client and the demo file acts as a server sending data.
Each tick, the demo driver reads a "packet" from the demo file and forwards it to the client, a "hack" to make it appear that the client is getting data from a server. I doubt that Epic would give out net code info, as much hacks could result. However, you can make native functions that handle whatever you want (I am planning on writing an advanced driver and info reader).