Ok. This article states last sighting was at the scrap yard.
States Wife knew there were no cameras at the station. Also, He
didn't trust that train station as there are many cars broken into. If he were to take that train he would borrow another car to leave at [the] station, said Ida.
States seat was pushed forward.
This is important:
"That absence of cameras also means there is no footage of Robert or his car entering the station.
Police dogs searched the area within a day of the cars discovery, as well as the grounds of Pilgrim State Psychiatric Center (though they did not sniff the Arrow Scrap yard),
but did not pick up his scent. Investigators also examined video from a nearby candy store which has a security cam, though that does not seem to have turned up any clues.
http://www.longisland.com/news/07-17-13/dix-hills-man-robert-mayer-missing-for-over-a-month.html