Overall this production is pseudo science and a fluff piece to make Dr. Lewis look good for the work that she did earlier in her career. While science has shown that people with DIDs can have an actual chemical changes/reaction in their brains, it does not change that people with DIDs are not serial killers. In fact, they usually do harm their selves and not others, or they are reclusive.
Serial killers are born, they are not created, but Dr. Lewis would say the opposite. Her opinions are fallacious because the trial of Shawcross, a serial murderer, shows he was not created by society, he was born that way. History shows that he had a 86 IQ and very early in his life, he was a schizoid psychopath. Real cases of DIDs are people who have traumatic experiences and create an imaginary friend to handle the problems so they do not have to deal with them. This is the same process children use to protect themselves from being alone or for putting blame when they do wrong.
If this production would have shown all sides of the story and presented all the evidence, then it could be a documentary, but it isn't because it hides the truth to make Dr. Lewis seem like a pioneer and a genius who was rejected by her peers.