All my experiences with gifted Elite APD upgrades have shown they are given priority above Gold members but below Elite members (and this is when the giftee is NOT travelling with the Elite gifter). This includes multiple instances when the Elite APD gifted upgrade has cleared before Gold RU's - Gold members travelling on separate bookings applying their own upgrades and in the same original booking class.
I think this is a glitch that Air NZ are aware of but have chosen not to do anything about.