I wondered if it would make sense to rent a litter so that friends of a wheelchair-bound person could bring them along. You'd need a team of 3, more likely 4, as a minimum, and some way to retrieve people if a carrier sprains something along the way.
Wikipedia says these are used for tourists in the Huangshan Mountains, so there's some precedent--though there the pros carry people. Liability issues would preclude that here.
Some of those steps are pretty steep.