This cache is not located at the posted coordinates! In order to procure the correct coordinates, you must complete the nearby Fieldale Textile Heritage Trail Adventure Lab. At each stage in the Adventure Lab, you will be asked a question; a correct answer will provide you with a portion of the coordinates.
You can find the Bonus Cache at N 36 4A.BC5 W 079 5D.E94
Take Heed! To acquire this cache, you will face a slight terrain challenge. Note the D/T ratings and attributes!