One of the most decorated rugby sevens players in history, Woodman-Wickliffe's move to the NRLW has been denied over a pre-existing ambassadorial deal involving promoting the rival code.
AAP revealed this week that the New Zealand star had agreed to a deal to join Newcastle for 2025, before it was blocked by the NRL due to a Rugby World Cup promotion.
The two-time Olympic champion was named the World Sevens player of the decade for the 2010s, while being picked in the World 15s team of the decade and winning two World Cups in the format.
The 33-year-old holds a lucrative global ambassador for Mastercard, who are a major Rugby World Cup sponsor.
Initial plans had included the winger missing one of the Knights' NRLW games to be at the Women's World Cup in England and fulfil a Mastercard promotion during the August-September tournament.
Woodman-Wickliffe was prepared to forego that trip, but could not agree to an NRL request to have the two-time Olympic champion's name and image removed from promotional marketing while the NRLW season was ongoing.
That has "disappointed" the Rugby League Players Association, who now want talks with the NRL about more flexibility for female players.
They believe the scenario is very different for women's players being involved in the promotion of other sports to men, given the average NRLW salary of $52,250.
"The NRLW is of a part-time professional nature and there are limited income earning opportunities for female athletes outside playing contracts," the RLPA's head of strategy and innovation Lina Caccamo told AAP.
"Unfortunately, and despite Portia and her management foregoing elements of her pre-existing deal, the NRL deemed it would not register Portia's contract unless further concessions were made.
"We wish Portia all the best and we are open to working with the NRL in the future on creating opportunities for cross-code collaboration.
"That will boost not only the profile of the NRLW, but also create new avenues for commercial growth, participation, and fan engagement in emerging markets."
NRLW contracting rules allow players to participate in other sports with club approval, making it possible for Newcastle's Sheridan Gallagher to play in the A-League Women's.
Tyla King, Stacey Waaka and Tenika Willison all played sevens at last year's Olympics, before their NRLW contracts kicked in and they joined the season late.
The NRL also allow flexibility in promotions of rival codes outside of the active-contract window of May to October, giving Cronulla's Tiana Penitani the ability to commentate on sevens.
League officials were keen to make the Woodman-Wickliffe deal work in a similar way, fully aware of her talent and ability to gain eyeballs in both Australia and New Zealand.
But they were concerned in-season promotion involving a rival code could have set a game-wide precedent for others.
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