Growing up in Maine, I remember my grandfather used to listen to his police scanner all the time, and some of the calls were very descriptive. Even a simple call from Dispatch to an officer in the field, indicating "minor car crash, one vehicle, female driver" would be enough for some crazy person to go off of. Plus, my contention that it's someone local who may have grabbed her, who knew the police, knew where they typically were/hung out, how long it would take for them to reach the crash area, etc, is what makes my theory very plausible, I feel.
However, that someone sick just happened to be listening to the police scanner around that location/time? Probably a stretch. However, a lot of people who live in remote areas have problems/issues; they're recluses for a reason. And don't forget that many criminals are very brazen and laugh at police and think it's a game. They do things in plain view, despite knowing there are surveillance cameras capturing their every move. Also, if you get a good ol' boy who's stupid/fearless and knows the lay of the land and the way police respond, I think it's very possible it was a race to get her that may have been exciting to him/them.
However, I think one of two things happened:
1) She wandered off to get cellphone reception, couldn't, knocked on someone's door and that person grabbed her.
2) She wandered off in search of reception, slipped/fell/passed out, was "out" for a spell, then someone found her and decided to keep her.
I hope it's neither. I'd rather die of freezing over four days than be held captive for years. Watching Disappeared is very disturbing. So many unresolved cases. What the hell's wrong with people?
BTW, just because some little old lady says the account was true, that the bus driver left and she went back into her house, doesn't mean she's being truthful. Anyone remember the based-on-a-true-story film Without A Trace? A son and eldery mother abducted and held a little boy captive for years. Women and the elderly can be just as sick and twisted as men. I would trust no one when it comes to these kinds of matters. You have to be skeptical of everyone. Perhaps that neighboring eyewitness was approached by Maura, and she struck her over the head with her cane and dragged her into her house. I'm not being funny. Anything's possible.