Thank you for your reply.
I called NZQA and they say they'll figure things out even without a stated GPA. It may or may not influence the assessment, go figure how they treat different academic approaches around the world.
They even said it is unlikely that they will have to contact the awarding institution, so that makes me hope they know what they are doing.
We will take the degree certificate on parchment to a JP, have it certified, and then send to NZQA for IQA assessment.
Hope it all will be worth it in the end.
Thank you for your reply and best luck with your application!