Looks like a beautiful place in which to have a “walkabout” - only one would want to be a bit more prepared than she was.
A map indicates there is really only one major road to Phoenix through that area. Why did she get off the road?
Sounds like she may have had some cognitive issues prior to getting lost and those issues caused her to become lost.
For example, she was way off course from her intended trip, ran out of gas, and abandoned her car.