AND it comes down to whether that truck was actually following her.
What a complex case.
One thing that points tp the truck being involved is the fact that they got two of the vehicles - but not that one.
but maybe it's as simple as they had a good camera and angle for the "bed cover" truck, and the car had bad film but was distinctive, but that third truck - the reason it's of interest, aside from it being behind her, is that likely they don't have a plate.
So again - we really don't know if the truck actually was following her, and that makes a huge difference in her possible route, doesn't it.