There is nothing hidden at the listed coordinates. This cache is a bonus for completing the Adventure Lab:
"kunanyi / Mount Wellington Summit".
Each completed stage of the Adventure Lab will reveal clues in order to solve the below:
The cache can be found at: S 42 53.(E+C)(AxC)(D-C) E147 14.(B+C-E)(E+A-D)(B-D)
Use your phone's native QR code scanner to open this Adventure in the Adventure Lab® mobile app, or use the following URL:
https://adventurelab.page.link/i5FQ