Wilkinson was found two weeks after going missing with wounds likely made by a machete.
Moananui represented himself at trial with the help of an amicus curiae, a court-appointed lawyer.
He made various legal challenges against the case, including one after he was convicted following the jury trial.
The final challenge was an application for a judicial review, which Moananui intended to serve on Prime Minister Jacinda Ardern, Governor-General Dame Patsy Reddy, Attorney-General David Parker and more.
But they never got that far, with a registrar putting it before Justice Francis Cooke, QC, to be considered.
The judge struck out the proceeding without hearing any legal arguments, finding it was an abuse of process.