The main question is who would dig a shaft over 100 feet deep, layer every 10 feet with oak logs and place layers of clay above some of the platforms? The bedrock isn't one solid mass; it is riddled with naturally-formed caverns.
Additionally, What was found in the swamp on Oak Island? Not quite, since the location of the original Money Pit is currently unknown and may remain as such forever.
Just 2 feet below the surface they found a layer of square cut stones, and ran into oak platforms every 10 feet.
William Castedo — David Fornetti's friend who only appeared in one episode of season 1.