The cache is not at the published co-ords. You will need to complete the 4 Lawrence of Arabia Lab Caches.
As you complete the Adventure Lab Cache keep a note of the numbers for A, B, C & D
This bonus cache can be found at: N50 42.ABC W002 14.(B-D)AD
Hope you enjoyed the Adventure.
At the Grave and Church you may not get phone signal so I have set an easy question and a 100,000m distance so you can answer when you get a phone signal.