The cache is not at the listed coordinates. In order to discover its location, you will need to complete the Adventure Lab "Oyster Farmer". You can start your adventure at the listed coordinates or select any of its locations as your starting point as they may be visited in any order.
To receive the coordinates for this bonus cache, check the journal page for each location and record the letter displayed. When you have all five letters, arrange them in alphabetical order and use the resulting code to access the Certitude checker.
You can validate your puzzle solution with certitude.
Adventure Labs are a type of Lab Cache. Originally developed to offer private or time-limited geocaches, in 2019 Geocaching HQ extended the Adventure Lab experiment globally with a select number of organisations and individuals given the chance to create Adventures. In 2020, this opportunity was offered to many more geocachers.
Finding Adventure Labs:
1. Download the Adventure Labs app.
2. Log in with your Geocaching.com account.
3. Select a nearby Adventure from the directory, or click here
4. Navigate to the Adventure location and follow the instructions in the app at each location.