Jamair, you may be right but I was under the impression that aeromedical work was AWK and not CHTR.
Even if it was CHTR I believe that a CASA dispensation is possible (and I think in this case probable) from the fuel requirements for flights to islands. If this was granted then it was a very poor decision from our regulators.
IIRC this point was debated at some length on one of the previous threads on the topic.