The container is not at the listed coords. You have to complete the Adventure Lab cache Bribie first:
https://adventurelab.page.link/1fxc
to work out the final coords. It might be a bit muddy on the track after rain. Don't forget to bring a TOTT to retrieve the cache and a pen to sign the log.
S 27 AB.CDE
E 152 FG.HIJ
Have fun!
Lbh jvyy arrq n GBGG naq n cra.