they might also used the whole stunt as a way to inform the public that they have the capability so that next time around at the interview goes "look kid, we do have the capability to unlock the phone, but it's costly, nasty, annoying for everyone involved and will put your refusal in a very very bad light in front of the judge and jury, why you don't just give the code and we tell the judge you cooperated?"
To be frank, the whole concept of "plea bargaining" in US law is a vulnerability, broadening the attack surface for many otherwise less harmful vulnerabilities.
they might also used the whole stunt as a way to inform the public that they have the capability so that next time around at the interview goes "look kid, we do have the capability to unlock the phone, but it's costly, nasty, annoying for everyone involved and will put your refusal in a very very bad light in front of the judge and jury, why you don't just give the code and we tell the judge you cooperated?"