She lost track of the trail on the way back? I don’t get it. Didn’t she just go back the way she came?
I know because I trained in the same desert terrain in north Scottsdale when I was younger and a marathoner.
It's easy to take a wrong turn on the desert floor when the trails aren't really marked.
Been there. Done that.
Darn birds and lizards ate up all the granola crumbs she left to mark the trail. That said, I can see it'd be easy to lose a trail- trails seldom look familiar on the way back unless you are very attentive in noting unusual natural features, creating unusual features with stacked rocks, or in leaving broken branches. You may see side rails from one direction you did not notice going the other direction, or the trail may not even be visible on open dry ground, and the light is different and deceiving.