All they'll get are some of the older players looking for a last payday, as with SL. I'd guess they'll probably have around half the side full of Aussies, so they'll compete round the edges. But a choice of more money to play out of PNG vs travelling to Europe is not a no-brainer at all. A lot will depend on how good the PNG side is, but its hard to see it not getting smashed on a regular basis, and once the novelty wears off no one will be interested. It will also disappear the moment Australian Government money dries up. Frankly its a stain on the actual competition, and it is only happening because of the huge subsidy from the government.
Perth is a more real threat to SL as that will require 30+ additional NRL players. If Arthur is the coach I'd expect him to tap a few SL players to reduce the need to grab players from other NRL sides.