The cyclist were on the very wide shoulder (off the road). The support car following them was most likely on the shoulder as well. The truck driver would have been able to see them well ahead of hitting them. He could have easily moved into the left lane ..... that is if he was looking at the road instead of a cell phone or book or tv. The fact that he veered into the shoulder to hit them seems to mean that he was not paying attention. I am thinking that skid marks on the road (or maybe no skid marks at all) would indicate whether or not he even saw them before veering off the road).
I live in a community where cycling is very common among the local community as well as tourist that come here to cycle. We all try to cooperate and share the roads. Of course there are some local arrogant millennials who resent the cyclist, actually they resent anyone who is not like them, and they whine and criticize, and recklessly speed in their pickup trucks, thinking of no one but themselves, believing they “own” the roads. The truth is that most of them pay little or no taxes that support the roads.
That's all fine and very commendable. However, if I can be blunt, from my experience, bicyclist who ride with a couple of feet from 4,000++ pound vehicles traveling at 40,50,60 or 85 mph are simply ignorant, nutz, have a death wish and are likly suicidal.
I've seen the results of people going under the wheels or struck by what is essentially 4,000 pound hammers. It's really ugly and a terrible way to die.