There are no doubts that there was SOME fuel in the aircraft.
There are doubts as to WHY that fuel was not in the correct tanks
One week after the accident, an air ambulance pilot was presented with 2 red Fuel Warning lights in flight, while the gauges told him there was over 100kg on board. The lights were right, he landed with hardly any fuel, the gauges STILL showing over 100kg
This explains nothing, but it does introduce grounds for possible mitigation for the accident.