I don't get why she would hang out with him for 5 days before going to the police. That part damages her credibility IMO.
This is not my opinion; more my nature of attempting to answer questions like these based on previous experiences. Again, not saying this is the case, or even that I think this is the case for Judkins situation:
Victims of DV in the past in similar situations as these have made the case/defense that they have little to no control in a relationship; and that especially when traveling to places unknown, can feel limited in means to "escape" their abuser. They "don't have money or means" to flee. If they do have a support system, they are not in driving distance and can't come get them. They will stay with the abuser until a time they are back in a known environment where they have access to money/vehicles/safe places they know they can go to not just get away, but be protected from their abuser. To add, women who are in an abusive relationship with a man tend not to be trusting of, or looking to, other strange men for help. When the option is the devil you know vs the devil you don't, they will get back in the car with the one she knows, much like this girl did.
I acknowledge people may not agree with the above, not only in this case, but in any case. Just putting out the information I've heard/experienced first hand and learned about with regards to power dynamics in relationships, including mentally/physically abusive ones. They are complex situations where rarely does logic apply, and often have a very strong mental component which has been built up over time, mostly revolving around feelings of powerlessness.