The dispatchers likely have a question sheet on the computer screen in front of them and the street address box on it has to be filled in, or the police dispatcher asks for it or some other bureaucratic reason exists in their minds.
Common sense should tell you how stupid it is to ask for an exact location from somebody who just told you they are lost.
If the kid knew where he was he would not be lost.(right?)
Tony B's son had the first question right. What is your last known location give a start, "About where do you think you are?" could work too.

But again, I think it is wrong to be trying to blame the operators. It was not just one person ignoring procedures that did this. Responsibility has to be with the people who actually had authority over the dispatchers.
To blame the 911 dispatchers instead of the 911 commissioners is like trying to blame the office receptionists for the collapse of AIG's banking business.