Autobahn corpse with lacerations on the neck-result of traffic accident, suicide of homicide?

A55-year-old man was found lifeless next to his car on an autobahn. On the left side of the neck there were huge gaping laceration type wounds. During the autopsy the injuries were found to partially have fine abrasions at the border and irregular margins of the wounds. The cause of death was named as injury-related polytrauma with inhalation of blood. During the further investigations atruck was seized, which showed sharp-edged damage to the metal on the right front of the vehicle. The injuries on the corpse were consistent with the ragged damaged edges on the truck so that this could be interpreted as aform of unusual and accident-related contact of the man with the truck