The geocache is not at the posted coordinates. Solve the puzzle which will get you very close to GZ. (Allow for forest geobounce!) Puzzle tips. I guess it is time I give you one. If you see a bunch of letters that don't make real words, most likely what you have in front of you is a cipher. Many of us know of a website to help with deciphering - geocachingtoolbox.com. In the hint, I am offering another option. The site helps for those instances when you don't know which cipher you are trying to solve for, actually highlighting a potential answer.
ONTRI SIHTR VIPTT RIHTR ZDGII SZETM RYMYC UTOPC KSOCU BDTZB LVDUZ BOSYT GSEEIL RUTHX SAZCP