Ask your friend to drill the Carolyn until it dries up. My personal advice is to double bag it, in case one of the bags comes off.
Drill hard, deep, and WIDE, leave that hole gaping so if any diamonds are hidden in there, they can been retrieved with a dirty shovel, or at least your arm. Drill that hole so big, that after that, no one will ever want to drill it again.
For the shareholders...