Kind of. The main characters were all minors when they committed murder, so there names and identities were never supposed to be released to the public. Their identities are released and they later change their names
A South Asían character discusses the difficulties of being the only Brown family in a majority white area in a way that makes it clear that the treatment she received was wrong
There are some tertiary characters with DID who are essentially avatars on Tumblr. I wouldn’t say that DID is misrepresented per se, but characters in the book seem not to take DID seriously.
The inciting incident of the book is a group of girls torturing and killing their classmate. The broad strokes of this incident are outlined in the beginning, and explained in more graphic detail towards the end