Why would there be a police record?
Celebrating the death of 3000+ US citizens is not illegal. They Muslims broke no law. It is evil, and generally “Bad form” as the British would say but not illegal.
Mr Trump was not the only person who saw this happen.
I lived in Hong Kong at the time and did not see it but I remember it being widely reported.
I do remember seeing people in the Middle East cheering and celebrating.
Again, I don't doubt there probably were nut jobs celebrating somewhere. I just don't believe Mr. Trump saw 1,000's in Jersey doing it. Like Mr. Carson, who now remembers it a Middle East footage, I think that's what Mr. Trump saw. He probably saw the footage from the Middle East and remembered it as being in Jersey.