Bill, while I agree with you, the simple fact is, an unauthorized person was giving clearance to aircraft, throw in the fact that it was a minor and while the kid did do a good job, there can only really be one result from this.
The fact that the pilots even accepted the instructions is kind of surprising as well.
Edit : I found the entire conversation
HERE where you can hear the controller making the majority of the calls.
If you wear the anorak with pride, you will recognize the voice as there have been many funny JFK ATC recording of him posted.