I would be questioning the 55 litre fuel burn for the 1 hour 50 something minute flight.
"The flight plan documented a planned altitude of 7,500 ft and a magnetic track of 082° direct to Elcho Island. The recorded fuel upload was 336 litres, with a planned fuel burn of 55 litres over the estimated flight time of 1 hour 52 minutes. The planned departure time was 1130."