I really can't stand that dude's videos, because they are super-overproduced, and everybody gushes over how uber talented the kids are based off them. So much studio magic going on in all of them, and he probably has parents throwing cash at him to teach their kids to be so 'awesome'. And this song, like others, I suspect some re-recording is done after the kids peace out (ETA: for instance the drums...I don't believe those are the kid's drums...likely programmed. He is playing different cymbals in the second half, switching from the hi-hat to riding the crash in the video, and ending rolls with crash cymbals, but the audio track is a steady beat on a ride or hi-hat, and sounds very much like a digital sample and not actually played and captured on mic.)
Most people just have no clue what goes on in a studio...given enough time, takes, and engineering talent you can make just about anybody sound as good as you want to.
Yes, I am a hater. Flame on.