score:7
You probably confused Papua New Guinea with West New Papua, a region that is indeed under Indonesian administration.
Papua New Guinea, on the other hand, was administrated by Australia from 1906 to 1975. It's north part was under control of the German Empire from 1884 to 1914, when it was surrendered to Australia. Papua New Guinea became self governing on December 1, 1973 and independent on September 16, 1975.
If your bet was actually about the island of New Guinea, then it's a tie.