The blame lies squarely in the flight deck of the A380.
Either the Captain didn't follow AF training or SOP's in this regard. Or he didn't follow plain common sense.
Or the blame lies with AF training (or lack thereof) as in the QF Bangkok over run incident.
Or the blame lies with AF rostering patterns that don't afford adequate rest for the crew in JFK.
I don't know what caused this, but whatever reasons they find, the blame most certainly lies in the AF flight deck for one reason or maybe another.