I know where you are coming from, however the witness states no drink or drugs were involved:
"...none of us smoked, none of us drunk"
Which is perhaps not so unlikely as the drivers "...had just passed their tests" and so they were probably in the 16-18-years-old age bracket. Maybe even all 16 bar the two 17-year-old drivers?
There is a dilemma here: If we want people to come forward, show their faces and go on the record with their paranormal/high-strangeness experiences - as opposed to endless anonymous posting on reddit etc - then should we take their testimony on face value? After all, he might very well find and read this thread.
From his face I would estimate this happened in the pre/early-internet age when being a teenager could mean long and boring days and nights - no WiFi, broadband, four channels on the tv etc - and we did go off on rather aimless expeditions on our mopeds and then later in our cars just to kill time and hang out away from parents. For example, aged 16/17 we used to go up to our local moor at night because of the local legends around Satanists meeting there (more likely pagans) and scare ourselves silly but no drink or drugs were involved.