Fighting with the Public School System - Advice?

I don't know if this is the best place to post this, but I am looking for any advice. My (soon to be) step son has ADHD, Bi-polar, and Oppositional Defiant Disorder. He is also on the Autism spectrum, and has toilet problems. Since day one the school system that he is in has not taken a liking to any of his issues. They don't even have an IEP for him, stating that it is not needed. Just a few weeks ago he was wrongfully restrained for his behavior though the school nurse testified that he showed no signs of danger to anyone or himself. He was taken out of class during a class project that he very much looked forward to so he could attempt to go potty. He was deeply hurt that he couldn't be apart of this, so he broke down in the hallway, and refused to talk, or cooperate. They literally dragged him to the office, during the whole time he was screaming "mommy" at the top of his lungs. When my fiancee got to the school after being called, she could hear him screaming outside the school. She had to almost break down the door to get in. When she arrived three women had him on the ground holding his arms, and legs. She took him in her arms, in which he immediately calmed down. Why did they go to this extreme? Why did they not just wait till after the project? They try to get him to go EVERY HOUR even if he has already gone. That is just excessive. Do they not realize how damaging it can be to isolate a child like that? Because of these issues (all of which we have pleaded from the school for help at home) instead of recommending a certified psychiatrist, or family counselor, they reported my fiancee to DCFS. A DCFS caseworker came out to her work, and only seen her for ten minutes. Didn't even stop by our home to see the kids. She only came out once, and three weeks later my fiancee gets a letter in the mail stating that she has been indicted for child abuse on the grounds of that her "mental health" poses a risk to our children. There is nothing even wrong with her. All she did was ask for help. So far the school has refused to give us a full report of the incident. We are now dealing with an unknown organization who is supposed to be our "help", yet they make threats to us. We are thinking about getting a lawyer to appeal the indictment, but not sure how to go about it, and also asking the police to get a report on the incident. We are not sure what to do. We feel like the school is doing everything to fight against us, because they don't know how to handle children with issues (We live in a small town). We have are backs against the wall, and fear that our children will eventually be taken away from us over the principal's arrogance. This isn't the first time she has tried to get us in trouble, but that is another story.