I would guess he is traveling at 45-50 MPH

Isn't that, right there, enough to tell you it's faked? Go rent a dirtbike, get it up to 45MPH, and slam on the brakes. See if you can stop in less than 10 feet. I'd say if it was real, we'd see his head going through the front windshield. If you put any useful crashpads in the van, you'd barely have enough room to fit the bike in the van. You'd also see the van kick forward from the impact of the bike in the van. That little thing called "momentum" doesn't appear to be conserved in that video...