it wasn’t his fault...maybe he was going too fast...but he manuvered his car around the blocking van and the people on the side of the road....he could not have seen people hiding behind the van, which was illegally parked there...
You can't outdrive your line of sight, which he did; the van to his left kept him from seeing the people making their way across the slow lane to the shoulder. (He knew he had to get off the shoulder because of the people there; it wasn't until he came past the van that he could see there were still people in a traffic lane. He cuts the wheel sharply to the left in response, but it's clearly too late.)
(To be clear, I am in no way absolving the dingbats who took it upon themselves to block a highway and then stand in it or the local authorities who apparently simply let this nonsense go on. I'm just pointing out that as with every traffic incident, the blame almost never falls squarely on one party.)