Have them address the letter to a Dr Paul Hofman.  He is the specialist in CAH at Starship Hospital and I am sure he will be the best person to have your child under whilst you holiday here Andrew.  

Best

Anne-Marie

PS:  Hope your holiday is a nice one.  You may like to contact the NZ CAH Support Group as Helen may be able to put you in touch with a few people in the North that you can call upon.  :)  She is actually in Christchurch, but runs the support group for the North and South island.