The FAA says you are ready when you pass your checkride.
Robinson says what their lawyers tell them to say.
The insurance company is in there somewhere, as well.
Rotorheads will never be satisfied with anything less than a background non-commercial pilots will rarely ever reach.
The reality is, of course, somewhere in between, and is strongly dependent on actual pilot skill and judgement.
It would be interesting to know if this was his first, or fiftieth, off airport night departure. Based on a certificate date of June 2021, it is easy to guess that might have been one of his first.
Occam's Razor also suggests pilot error, but there is no way to know for certain. Perhaps it was some type of catastrophic failure that many like to assign to Robinson helicopters.
The real question is: why do they not teach pilots how to properly and safely do things with helicopters that helicopters actually do? In the US, it is very likely that a newly minted private pilot has made the vast majority of their flights paved runway to paved runway, performed their minimal confined space operations in a farmer's field that was by no means confined, have very little night experience, and have performed zero off airport operations at night.
I am the very definition of the guy "with a bit of cash, master of my business domain, life/experience gradient", etc. I was quite disappointed, sometimes bordering on the appalled, by the instruction I was not receiving. I was lucky in that I mostly (not entirely, of course, and I am ever watchful) knew what I didn't know, and thus recognized the need for more and better instruction, something which ultimately lead me to push on to a commercial rating. How many don't know what they don't know?
And even with a newly minted commercial certificate I was left hanging. For instance, I never flew in rain (in a helicopter), not once, until after I had a commercial rating! Yes, it's bad for the blade paint, but worse for the student. Never once when the weather is at Class G minimums. But I was asked to do both when actually working as a pilot. Thankfully I had my fixed wing training to partially fall back on. My private fixed wing training was much better in some areas. There are certain institutional fears found in helicopter training that are, IMHO, misplaced. VFR night and weather conditions were much more extensively flown in during fixed wing training. This needs to change where primary helicopter instruction is concerned.
And the idea that you should not fly with your family at night is ludicrous. If the weather is reasonably VFR, and the man and machine so certified, this should not be a great challenge if flown paved runway to paved runway. But, certainly, night off-airport op's are next level stuff. I'd be interested to know if anyone here ever received formal training in that outside of the military or public safety/HEMS.