I hate stories like this. It's so sad, especially when there are such simple solutions, as you say, hikermor.
Did I read it right when I assume that this all happened on the same day? They found them the same day they were reported lost, so I wonder how long were they lost? I'd like to expect more from my fellow Scout leaders than deathly dehydration in a day. I've never been to Arizona so might be way off base, but even here in Ontario, we know better than to get caught out in heat like that, never mind without being prepared with water and shelter.
Such a shame.