I flew the St. Maarten police helicopter for 2 years, and we were allowed to fly night VFR, indeed most of our flying was at night.
I can not count the times I had to say no to a night flight to different islands, and it was usually an "emergency" of some sort.
He definitely got in over his head, and as has been mentioned he only had a private license. The odd part here is that he flew for (and started, and was the ops manager of) leeward island helicopters.
Leeward Islands Helicopters St.Maarrten Helicopter Charters Helicopter Flights Helicopter Tours St.Maarten St.Martin Anguilla Saba St.Barth Statia
Reading their website it seems he intended to do 2 flights that night, one to bring over a patient, and the other to bring over the family. Choosing to fly a medevac for a heart attack victim is one thing, but to also fly his family on a second flight....
And the crash site, 12-14nm from Saba is the halfway point between the islands, so should be the darkest spot...Saba is not a big island, with very flew lights on the side facing St. Maarten.