Some very lucky people there!
A brilliant testimony of why you should never, and I do mean
never stand behind a vehicle when at the roadside (or between a car and trailer) That was one of the very first ever lessons I had when I started on Traffic Patrol.
It has certainly saved me from serious injury, or worse, at least 3 times over the years.
I have a theory why this sort of thing happens (especially on motorways at night) Drivers go into a semi sleep state, their brain "sees" a vehicle ahead on the road thats NOT "on the road" and they "tuck into" the same lane to follow it
. In many such instances there is never any indication of braking prior to impact, which I think does tend to support my theory. Doesn't make it any less traumatic fio those involved though.