Automotive main electrical systems are usually 12VDC. ...
Yes, that's why I said "24 volts" twice, to let everyone know it wasn't a typo or misunderstanding.
... 120 volt work light being involved would have raised my suspicion enough to warrant looking into it further.
I would have liked to have seen it investigated, too -- if it was a 24-volt fatality, it would have been one for the books.
But everybody did their job, and their job didn't include investigating.
The firefighters rendered the scene safe for the paramedics, and their job was done. There was no fire; they didn't suspect arson, and they didn't investigate.
The paramedics declared the guy was "not a viable candidate for resuscitation", (they're not legally empowered to say "dead") but paramedics don't investigate.
The cops didn't suspect a crime and didn't investigate.
The hospital declared the guy DOA and turned it over to the coroner.
The coroner ruled this death "accidental", didn't suspect foul play, and didn't investigate.
Apparently, there needed to be the likelihood of a felony and the possibility of sending someone to prison before an investigation could be initiated. Mere public safety and deeper scientific/medical understanding of electrical trauma doesn't meet the threshold.