No I don't think so, it appears to be edited from an actual video. I don't think Ai is capable of making believable scenes like this, look at the hands. They all have the right amount of fingers, the vocals are cut so that their mouth movements kind of match the vocals, but they cut around it so they never have to show more than a word or two. I'm guessing it's cut from a real video.
Ai is really bad at fingers, I don't think it could do a full brass band without something going horribly wrong. I could be wrong, but I think it's editing.