I don't see why you think the license and insurance on the car which was ran into makes any difference.  Those are infractions, and would likely have their own consequences, but they have nothing to do with the pickup driver failing to yield right of way and running into something.

Generally speaking, it is the driver's responsibility to avoid plowing into objects, vehicles, animals, or persons.   A stop sign is installed to notify the driver of the potential for other vehicles to be using the space immediately after the stop sign, and to notify them that it is their responsibility to avoid plowing into said vehicles. 

I have never seen anything in Kansas Statues which said 'the driver of a pickup truck with a biggassed bull guard on front is granted the right to plow into any vehicle which is driven without proper paperwork.'