Of course they would have insurance, but the insurer wouldn't pay out more than they legally had to. Why should they?
Aussie citizens or not - it was a domestic flight and subject to PNG law - which limits payout from the carrier to 30,000 Kina. The nationality of those killed is irrelevant.
The litigation lawyers you refer to Mach therefore have nowhere to go against APNG. Of course if they can find someone else to blame then they may be able to get somewhere. Hence they would probably be very interested in the outcome of the accident investigations.
I don't like their chances.
No offence Mach, but personally I'm a bit over insurance bashing sentiments from those who perhaps aren't armed with the facts.
TB