'Five miles isn't a long hike for an experienced hiker. If it was only two miles, that's even easier. Here are two possible scenarios.
Scenario 1
-Hughes drives to the campsite, possibly sets up camp, goes hiking.
-Then at some point, something happens (medical, psychological, pharmacological, or an outside threat such as an attacker). She dumps things from car into campsite and drives off.
-She has a car crash where the car was found. She then walks off from there, bruised, barefoot, and possibly disoriented. Someone asks her how she's doing but she refuses medical assistance.
(In this scenario, what isn't clear is what led the campsite to be so disheveled. It also sounds like extra things were dumped out of the car.)
Scenario 2
-Hughes drives to the campsite, sets up camp, goes hiking.
-She drives off to find a particular car and has an accident.
-Barefoot and bruised, she walks back to the campsite and goes through her things or throws them around. Someone sees her near there, but she refuses medical assistance.
(In this scenario, it's still unclear exactly why the campsite was disheveled or why she didn't just hunker down, but the accident itself might provide some explanation if it caused her to be disoriented or confused.)
To choose between these two scenarios, one would need more details about where she was seen barefoot, the exact condition of the campsite, where the tracking dogs thought she went, etc. Of course, some third thing might've happened.
Oops, I need to proofread better. In the first scenario, I meant to type "she drives off to find a particular trailhead and has an accident."