Cache is not at the listed coordinates
This is a bonus physical cache that you must complete the Heart of the Mallee Adventure Lab in order to find. The adventure lab takes you to just a few of the historic and artistic locations in the mallee town of Karoonda.
You can play the adventure here.
During the completion of the Adventure Lab you will collect pieces of the cache coordinates as you answer questions at each of the five locations within this historic mallee town.