With them alternating between climbing and belaying off, the fall would just be painful, probably not deadly but you still need to climb a third of a mile straight up. That requires that you be in better shape that I am in
What is the base altitude. From my experiences in the Tetons and the Rockies I can say, if you get over a few thousand feet above sea level, air starts be be hard to come by. Up around 9000' they just don't have much.
I too was thinking of a parachute to go home at the end of the day, but then you've just got 1 more thing strapped to your back (plus a reserve) to climb up there with.
Oh, Well; such is the unintended cost of "wireless" communication. Better them that me...any day of the week.