It is supposed that the "metadata" collected could help you to to so.
Every time a phone connects to any station it sends a message "hello, this is number XXXXX trying to log on any net, any chance?".
Then the station checks number XXX with it´s operator and accepts or not the connection and the phone user can use the net, may it be his company or another one with agreements in the area.
IF you can access the data from the stations then YES. you can track back the location of a phone.
Problem is that legally you are not able to access this metadata without a court mandate for the investigation of a crime, therefore even if the company gets to track the number you wanted the info is useless (unless you are a kind of person who I do not know but ho has developed a set of skills that I prefer you not to use to find me and punish me...) (Yes, it is a TAKEN joke).
NSA and military services have been using it for ages, even you can set a fake station to get the phones in an area to "connect" to your station and this way not just track but even record all the traffic assuming you have the $$$$ to prepare such operation.
Last time I was offered a mobile phone connection point in the middle of nowhere it was about 4500€ a week with a mobile station and the technicians in a truck with a generator by a commercial company and without the option to track locations and record traffic.
I dare to say that a shadow agency could get it at least as cheap as that if the objective if worth.
