For three friends, an eagerly anticipated dream adventure to the Grand Canyon becomes a nightmare

By Ray Sanchez, Rebekah Riess, CNN (CNN) — A foreboding sky rises high over a selfie taken by a smiling John Giusti before the jagged, staircase-like ridges of the Grand Canyon on the first day of a dream hiking trip with two buddies. Standing before the canyon’s sheer cliffs, plunging up to a mile down,