Well - the advice would depend on the country but rabbits are not native to New Zealand, and rather than being 'wild', ought to be considered a feral animal. Through much of the region, they are considered a pest, and there's significant issues caused by them, and measures to control the population. Here's the advice given by the New Zealand government and it comes down to "they're bad for farms, they're bad for native ecosystems, and we're trying to eliminate them".
Releasing the rabbit into the wild is the worst thing you can do. Predators aside - many of which are 'pests' in their own right and also eat native wildlife, they face the risk of diseases, natural and spread for population control and hunting by various means including being hunted down by dogs.
Basically if you're paranoid about things happening to your rabbit, they might be true.
Now that I'm done with the scary parts, have you thought of contacting your local animal rescue, and specifically a rescue specialising in rabbits? They'd likely have knowledge about rabbits and be able to advice you on the right thing to do, or rehome the rabbit if you're over your head. Your rabbit will probably never be 'wild' and never has been, but that feels like the best chance for a healthy happy life for the critter.