Disclaimer: I haven't read any of the books, but I am finding the discussion interesting.
On the brain scan showing signs reversed, I had a friend who did have a situation in this. She had secondary cancer in her brain, and a scan showed huge patches where it was just taking over. She had 6 weeks of treatment (and prayer, but don't please sidetrack debating this) and she had a follow-up scan on the Friday. First thing Monday morning she had the consultant on the phone gibbering at her that he'd never seen such an improvement and it was amazing. The cancer had gone from pretty much in every part of the brain down to a few tiny spots.
But it didn't last unfortunately and she did die a couple of years later.
Obviously this is a different illness, and the subsequent scan 3 months later showed that the cancer was growing again, but the medics didn't treat it as anything but an individual phenomena. Medicine, after all, is an inexact science and things do act differently in different bodies.
So I can believe that in the first instant the consultant would be "that's amazing, keep going." If subsequent scans showed further improvement though, then I would expect more to be looked into. But it does happen sometimes - look at Steven Hawkins, in 1963 he was given a life expectancy of 2 years.
The other thing that occurs to me is something I've noticed in people that they often attribute their own personal failings to other people. So people who lie, assume others are lying to them; people who manipulate, assume they're being manipulated; gossipers assume others are gossiping about them etc
And they often are incredibly judgemental (especially taking on a victim's role) and indignant about the fact that others may have done these things to them.
So her suspicion of others may well be down the fact she knows that she is untrustworthy herself so is projecting her attributes onto other people. She knows herself how untrustworthy other people can be while appearing "nice" people, so she's naturally distrusting.
I can't see them getting any comeuppance, except in not able to publish book #4 unfortunately though.