Fifita played a starring role during the Sharks' premiership charge and was arguably the best player on the field during the club's breakthrough grand final win over the Melbourne Storm on Sunday night.
Despite this, the NRL firmly instructed Australia's four-member selection panel to overlook Fifita and Parramatta winger Semi Radradra from its 24-man Four Nations squad, which was announced on Tuesday.
The hard-line stance is supported by Kangaroos coach Mal Meninga and was on Wednesday backed by senior Kangaroos star Johnathan Thurston.
"It's a stance the game is taking, we want to see more people and fans come through the gates and more people watching our game," Thurston said.
"If the game feels as though that's the best decision to make, then as a senior player I fully appreciate what the game is doing and stand up for that."
Fifita was also overlooked for Luke Lewis for man of the match in the grand final, however NRL chief executive Todd Greenberg dismissed suggestions he was ruled out of the running for the Clive Churchill Medal.
Greenberg said Fifita wasn't considered for a green and gold jumper because of his history of poor behaviour, including abusing a referee at a junior match last year for which he was suspended for six weeks.
The NRL Integrity Unit is also still carrying out an investigation into Fifita's relationship with convicted one-punch killer Kieran Loveridge after police last month warned him against consorting with criminals.
Radradra has flagged his intention to plead not guilty to charges of domestic violence against his former partner.
After the Fijian-born winger made his controversial debut in the mid-year Test against New Zealand, he was replaced by Penrith's Josh Mansour for the Four Nations.
Greenberg said while he wasn't pre-judging Radradra's case, he was concerned it would prove a distraction.
Fifita has previously threatened to walk away from the NRL.
In 2013, he was spotted meeting with then Wallabies coach Ewen McKenzie about moving to the 15-man code before eventually re-signing with Cronulla following a botched deal with the Bulldogs.
