There is only one thing that is clear in this complex and horrible situation - your friend is not behaving the right way with her son. She is giving in. She does not owe him reports on which health providers she is or is not seeing - that is her private life. She also should definitely not have written the list of 10 things. He is a bottomless pit - he would never be satisfied by her giving in to his demands. Nothing would ever be good enough. Nothing would ever be sufficient. So that route is doomed. If your friend takes a firm stand that is in line with her beliefs, things MIGHT get better, but if she does not take a firm stands, things for sure WON'T get any better.

Say, when he asked her to list 10 things she has done to MIStreat them, she should have answered with:

"Well, that I cannot come up with since I have not mistreated you, but I sure can come up with a list of 10 things I have done treating you rather nicely. They are:
1.
2.
3.
..."