I think we've strayed a bit from the path.
It seems that the aircraft was legitimately ferried from the US to the Philippines. This leg seems to be well documented and understood.
The Alaska - Philippines leg may have required long range tanks. Once it got to the Philippines it could go anywhere in Asia (including Australia) on standard tanks. An ex Airline captain I know owns one in Thailand. He flies it to Melb twice a year to visit the grandkids with (from memory) 1 fuel stop.
At the Philippines it was handed to a new owner whose identity is unknown and (presumably) the ferry company took business class airfares back to the USA with their ferry tank tucked under their arm.
The leg from Philippines to Woollongong seems to be the mystery. The port of entry into Australia is not known to us, nor the route to the 'gong. Nor why you'd use a freakin Merlin III for 35 lousy kilograms of drugs. Let alone why you'd choose to unload them in Woollongong rather than Upper Kumbuckta West.
I would have thought that if the Merlin III was intended for drug running you'd put 350kg of drugs in it - not 35 kg and land & unload it somewhere remote.