Also the attack can be performed multiple times and if a person travels it could narrow down the possibilities quite a lot.
Let's say they travel between NY and LA, how many sources of data will you need to know who was in NY on a specific date and LA on a second date? Feels like only the government can reasonably locate that.
They had an example of the attack getting two locations back, Las Vegas and San Francisco.
So the target is somewhere in the many thousand square miles in the circle that encompasses almost half the US!