Well, even without anyone physically showing up, they had made the decision to tell the potential "unconfirmed stalker" the private information.
So the court order wasn't going to be needed at this library.
And you know this because? You have no idea if they knew it was the police or your potential "unconfirmed stalker."
Their Caller ID may have identified them as the local police. Obviously they called some number back. Do you know if they did that not knowing who's it was or did they check it out and find it out to be the local PD's number?
You're making assumptions to support your theory.