In general a HUGE factor in the decision is whether or not you REALLY think that help will come looking for you.
In the situation described, it sounds like help would indeed have come ... eventually. Still, the people involved clearly felt they were prepared sufficiently to "self-rescue" and I don't have any problems with that.
I too would probably have stuck to the road, but then again, they knew about the terrain they'd be facing. I'm a sure thing kind of guy.
Ken K.