Tracking without Tracking?
They have to track the cell phone signal / phone number / SIM card - which means of course it tracks the number since it they are tied together - then they would have to discard the BOTH pieces of data and assign a random tracking to to ID that phone - which of course they would have to KNOW to track back to the same SIM / phone in order to avoid duplicates - which means of course they still have to track those numbers in order to actually track the phone.
They may not KNOW the name of the owner - but they WILL have to know the SIM / Phone number since the whole cell system has to know where that phone is at all times when it is turned on and they are just using local receivers to track the phone more precisely within the mall.
Since all this data is kept and analyzed then of course it is also subject to a court order to give exact detailed information to the government / police if they ask for it given the above info on how cell tracking has to work.