Waqa's parents will be bloody lucky to remember his name after he retires, let alone the greater Rugby League audience. He is a completely average winger with the added bonus of the occasional brain explosion. During this tournament he has looked so far out of depth playing at centre, or further to the point; away from the Melbourne Storm try delivery system.
As far as these four 'walking into' the Australian side, either now or in the future, you are deadset in some sort of rlwc induced fantasy. All of these players have pretty glaring deficiencies in their games, and, with the exception Koroibete, none of them are exactly young. How would Kev (24) ever push Inglis (26) or Hayne (25) for the fullback spot? Or at what stage in his late twenties do you expect Waqa (27) to snatch a centre or wing spot from any Australian incumbent? Uate has been there before and could clearly be there again, but there is a damn good reason selectors went off him for both the SOO side and the Test side.
I am the biggest fan of Kev & Uate, and love watching this Fijian side play, but your claims are ludicrous. Waqa is one of the weakest outside backs in their squad ffs.