He actually did run quite some distance off the runway. Any vehicles anywhere near the runway would have been an unacceptable hazard.
He did extremely well, with better RT than some PPLs. But though he had no formal training, I suspect he wasn't entirely new to controlling a light aircraft (with 'hands on' from the RH seat) as he was an experienced 'passenger'. Of course, he'd presumably never landed before which is what makes his feat so remarkable.