Hmm, I think you're drawing too strong a conclusion there. Vanuatu can just as easily say that they're complying with sections 16.3 (a) and 10.3 in lodging their protest, and that the only issue at stake is the mechanism of the protest process/procedure.
I do agree with you though that focusing on that process is the best chance for any appeal to potentially succeed.
Vanuatu's protest does not comply with 16.3(a) because they are not complying with the Pacific Games regulations. A protest needs to comply with both sets of rules in order to be legally valid as per 16.3(a).
I have just read the OFC disciplinary committee decision document - it makes the 'process argument' even stronger for NZF.
Paragraph 14 (email from OFC on the topic of Pacific Games regs vs FIFA Olympic regs):
After receiving the second letter from VFF, OFC have accepted VFF's protest due to the significance this context [sic].
As a consequence, FIFA rules regarding the protest will take precedence over the Pacific Games Rules.
Say whaaaaat?
OFC is admitting that they have shifted the goalposts on how protests are dealt with due to "the significance this context." The FIFA Olympic regulations state that those regulations must be followed and the respective local regulations must also be followed. You can not abandon the Pacific Games regulations due to "the significance this context".
This topic is discussed again on pages 16 and 17 under the heading 'Applicability of FIFA rules'. All OFC does is to cite Article 16 of the FIFA Olympic regulations. They have even quoted the exact paragraph (16.3a) which states that both sets of regulations must be followed.
So from a legal perspective this would be a clear cut victory for New Zealand. Any credible legal arbitration would deem the entire OFC process to be null and void as a result of those paragraphs. There is of course still the question of institutional politics - will NZF even have access to credible legal arbitration? Through OFC? No. Through FIFA? Maybe (the organisation is changing rapidly). Through CAS? Likely, but at what cost?
Finally there is the issue of integrity. From what I can tell NZF knew there was some degree of doubt over those players but decided that the Pacific Games rules gave them the security that any challenges would be made ahead of time, in which case they would just remove the challenged players if need be. It is certainly a dubious approach (though legally valid) but before making an ethical judgement I would want to know the full context of how FIFA dispensations work. Is there integrity and consistency to that process or is it a game of roll the dice with Sepp Blatter? What is the FIFA decision making criteria on whether to grant special dispensation and is this a transparent process? If the dispensations are given as a matter of course then why have the rule in the first place?
But just to clarify, none of that stuff has an effect on the legal appeal. The OFC's case has no legal credibility whatsoever due to paragraphs 14, 51 and 52 of their own decision document.