Anyone else in this position would do no such thing.

Trump is in this position because he wants to do this AT LARGE SCALE.

He doesn't care about being cruel to a couple of people, it's about getting the precedent and go-ahead to deport millions of people. What happens to this one guy is much less important than the precedent of at the very least being able to deport without due process. Ideally he and his friends would like to be able to deport without courts being able to order them to bring people back after the fact so they can just purge a bunch of people from the country.

But, you know, Trump is always right! What does backtrack even mean? /s obviously 😵

It's not even about narcissism. If this man gets back, he gets to talk to media about his experiences, which will likely turn a lot of people against Trump's plans. Trump's fascism is contingent on people being complacent about the things he's doing