The cache is not at the listed co-ordinates.
In Maori mythology, Ikaroa is the long fish that gave birth to all the stars in the Milky Way or the Mother Goddess of all the stars – ornaments of the Sky God Ika-Roa is also an alternative name for the Milky Way. (Source https://en.wikipedia.org/wiki/Ika-Roa), Some might then relate this to a flying fish.
The listed co-ordinates are for the local Post Office.
You should all be familiar with the local Postman and his obsession for numbers, particularly the Smith number 2232322932069165049. He sometimes spends a little too much time at the bakery as he does like cakes and Pies which caused him to be forgetful and make an incorrect delivery, Can you help him retrieve it? All he can remember after lunch is per below along with something to do with the Ika-Roa at GZ.
D 5. 12, 14, 7, 18
A (1+19). 16, 2, (15+4), 10