No, the last verification by camera was further north in Stagecoach.Stagecoach to the Luning Rest Area is approx. 2-1/2 hours and so it's quite possible they stopped there for a rest break. There are really only two scenarios at this point. Either they took a wrong turn sometime after leaving Luning and are stuck in the middle of nowhere, or they ran into some very bad people (perhaps at the Luning Rest Area) and they were abducted and either forced to drive or incapacitated. There is no proof that Ron was driving and Bev was in passenger seat in that grainy picture taken south of the Luning Rest Area. Or am I mistaken and it's 100% verified that the Barkers were driving the RV in Luning?
IIRC the image of the vehicles passing along the highway near Luning came from a home camera...