One calls a tow truck and does not leave anyone alone on a Texas highway at night.

Why did she 'take off instead"?

And please, anyone being chased will of course be 'disoriented and confused'. Unless there's some history of erratic behaviour, surely the detectives went through her computer?

And as to she ran her car off the road...that smells to high heaven, sounds more like she was being chased or as you wrote, "The paint transfer...leading to the theory that she was intentionally run off the road."

And her apology seems to point to at the very least 'knowing too much' about some kind of criminal activity.

Lastly, why no dogs?