Hi,
My New Zealand was thought to not have any reproductive parts, but the vet was inexperienced and she was to young and fat to be able to move the fat out of the way and see them. She had a CT 6 months ago (2 years old) and the new vet found her system and took it out. Sometimes the bun is too young or has too much fat to see them haha. They are definitely in there, take it to an experienced rabbit savvy vet and they will be able to fix him. They can also do an X-ray to see where they are in them, it is very unlikely his was born with nothing.

Have you ever litter trained him? So you don’t immediately give him the whole space to roam. You need to start by having him in an xpen with his litter box, then as he learns to use it, then you slowly give him more room as he keeps using the litter box, but if he stops using it then you need to go small then bigger if he learns. having him/her not fixed will increase the chance of his litter box habits not being kept and he will want to keep marking his territory so it is best to have him fixed. Make sure you have hay in there so he will eat and poop in the same space and make the connection that pottying is done in the litter box. Make sure to give him small healthy treats when he uses the litter box so he will get positive reinforcement.

Rabbits like dogs and cats can be litter trained. I’m pretty sure there’s a whole section on it on the BUNNY INFO part of Binkybunny. So funny that the vet couldn’t tell the gender, but as bunny house said maybe the vet wasn’t that experienced