It sounds like he was detained by law enforcement to me. He was quickly released because he was probably polite and cooperative. Folks that are detained without probable cause have every reason not to be polite and cooperative.
I'm hoping that the cops were apologetic from the start. "We aren't detaining you and you are free to go. We received a nutty call that your daughter's behavior suggested she might be a victim of human trafficking. Is there any information you can give us to confirm how silly that is? Once again, you are free to go but we would appreciate your help in dispelling this concern from a well-meaning flight attendant."
If we are okay with detaining folks based on profiling, let's go ahead and pull over young kids in expensive cars, gold jewelry, and no apparent source of income. Occasionally, we might nab a drug dealer. For those that are innocent, they should just be polite and cooperative. No harm, no foul.
Airline security measures should concentrate on making air travel safe, nothing more. While convenient, domestic air travel shouldn't be used as an extended traffic stop.