Looks like the helmet did ride up a bit. Note the largely symetrical bruises above the eyes, as if this is where the pads of the open-faced helmet were pushed into the flesh. The strange marks across the cheek is probably from the creases in the plastic where he hit it, but his scalp is largely clear. But the real clue is the bruising on the chin, as the plastic wrap tried to pull the helmet off his head, the chin cup was forced up, leaving a characteristic mark. On the left side of his jawline you can even see the outline of the strap.