If you look at the video slowly from 0.3 to 0.5 , you’ll see that the first line of pallets on the headboard are double stacked.
Looks like the bottom pallet has collapsed, sending the top one out onto the road.
And yes I’ll agree, he does seem to be tonking it round that bend, (Nameplate in the windscreen says it all) 
looks like the plastic wrap on the bottom pallet has given way, therefore no support for the top one.
Gotta say that the people in the car were ■■■■ lucky, could’ve been worse !