Well... I'm back (not that anyone cares, but final exams consumed my life!) but I think it would be possible to avoid a Cave of Sighs temple guard. For example a contestant could enter the Room of the Three Gargoyles, go down, and enter the Pit of Despair from the top entrance and avoid the temple guard hidden in the bottom corner. For a contestant to be caught, the temple guard would have to climb the Cave himself!