Good luck hiring and training enough Australian soldiers with $600M, over 10 years, to counter the two million of the Chinese army.
And I'm afraid you aren't paying attention to the diplomatic news. Less than a year after the PNG bid was accepted for the NRL, PNG signed a formal military alliance with Australia on 6th October 2025. They do not have an alliance with any other nation. It just went into formal effect July this year.
The Australian Govt has veto power on the Chiefs funding - they can withdraw funding if PNG sets up security arrangement with countries outside the Pacific, without consulting Australia. NRL would also be compelled to remove the team.
The article you quoted is from 2019.