If you were passing near NLK at some time when there were no scheduled flights, the aerodrome may not have anyone in attendance. You could probably have them on standby, but I imagine there would be a fee for that - and why not?
But if you have HF contact with Auckland and were to have an emergency, they are very efficient and would rouse someone soon enough to attend the airport.
But as others have said, when the weather is marginal, it can go to bad very quickly. The aerodrome operators there are pretty good at calling it for what it is and if pressed, would probably give you a fair idea of your chances of making a successful approach. Even though they may not be pilots, they have seen it all before.