I suggest there would be little local involvement in the execution let alone planning of this glorious plot. The Mafia in Australia and the South American supplier (assuming this was trans-shipped Coke) are experienced in their business and would have little need to insert a bunch of wantoks into the movement of the gear from a boat or shipping container onto a truck out to the airstrip - it would be fairly easy to put your own couple of guys in-county for a few months prior to the day or two it would take to do the operation. I can straight-up think of two legit reasons to lengthen the local landowner's strip for him without raising any suspicions (but hey I'm not running a smuggling course).
On the other hand, despite half a billion dollars worth of coke being at stake, Mario and the guys allowing the half arsed nature of the Mareeba / 402 phase of this plot to proceed could mean that they were actually not as bright as they thought they were.
However, if this was an entirely PNG-designed plan, then burning aircraft parked in the bushes and pure chaos all round would be far more likely
