I was always under the impression that a scrub meant front wheel pointing down. To me (and when I saw it in 8 ) he tabled over a jump that was set up so he came very close to the ground.
A scrub is just getting flat or sideways and cutting the pop out of the lip so you don't land as far down the line. He pumped it, and put himself in a position that he'd be unable to ride it away without being flat. It's a scrub.