I was there during this, literally text my wife when got notice and said “I do not know when I will be able to text next so keep an eye on your email”.

I don't buy their reasoning.

With all the mobile tracking tech, I would have thought that it would have been easier to catch the person if they had a working phone on them.

I assume that they weren't attempting to track him. They were trying to prevent the communication between the conspirators so that they can't coordinate his escape or organize an uprising to aid his escape. Suffice to say, the telecom networks and the internet service are fair game to them and they don't think twice about interfering with it for any reason.