I can only tell how the T-mobile system works. They had a device called a LMU that was placed in most of the nodes that most of the time showed LE were I was within a few feet. I had to call into 911 and test each cell site when I finished moving them to LTE. Sometimes the dispatch would jus say “you’re veins the dealership on so and so, but sometimes the person would be very specific and say “you’re 23 feet from the corner of this and that, which I thought was crazy but they were correct. Now so of my calls were to fix a LMU or the antenna but they always had enough to get where we were or it was a emergency and the fcc could get involved so we made it happen. I was on one of those calls in Reno NV and they dispatched 2 of us. The area was out in the sticks so I’m guessing there was only 1 LMU at this section of freeway and it needed to stay up for legal reasons.
Now I’m not sure if this is the type of info the 2000 mule folks had, but LE certainly has access to the LMU information if they have a warrant.
Hope this explains at least this one device that is engineered into the cell sites for tracking purposes.