A lot of other people don't really believe us when we say our kid did something that drastic/severe/dangerous. I had a sp ed teacher once ask me why I thought it was a big deal that my 11yo was waking up in the middle of the night and going for a 2 hr walk in the dark. Alone. 11yo. 2 am. in the dark. No one knew where he was. What was the big deal?
I called and asked her boss why the new elem school sp ed teacher thought it was perfectly fine for a child to get up and go for a walk all alone at 2 am? Why the teacher didn't have the judgement to know that the child could be hurt, killed or blamed for almost anything and we would have no way to find him or to defend him if someone else was hurt and he got blamed? If I had gone out and left my 11yo home alone, sound asleep at 2 am, I could have been charged with neglect, endangerment or toher things, but for him to go out on his own was just fine. Gives you some idea of the level of common sense that not all of these people have.
How are the neighbors reacting? That would be a HUGE fear of mine, mostly because I lived in a town where lawsuits were the hobby and neighbors were quick to call their atty's. I am sure the parents are upset, but do they realize the level of abuse that has happened? Are they taking their kids for help or are they just expecting the child to "get over it" or treat it as "kids exploring their bodies" or some other stupidity? If other parents have not called cps, then cps may think you are crying wolf for attention. You, and/or the tdocs involved with your family may need to report that the other kids have been reported if the parents have not reported it. Kids don't just forget. Trust me.
Many will think "what do you want me to do?" when you report a girl has abused another child. They will see it differently if the report is that a girl was abused by another child. I don't know why, but so many think girls can't be the sexual predator, or if the girl is older and a boy is involved it is okay. Same idiots see 15yo boys who have sex with teachers as being "lucky".
Push them to see how serious it is. Even if you have to go and push your daughter until she spills the whole ugly mess of what she did to someone at the phsop or Residential Treatment Center (RTC). When it spews out of the child, it will be seen as different by that person. They will see the hate and need for power/control that is the reason for her actions.
Don't let them tell you it isn't a big deal. Just as we tell our kids - tell somoene and keep telling people until they stop it. I know many kids who told people who did nothing or didn't believe it and they never again spoke of it. I worked hard to get my kids to keep telling. If the first person or dozen people are too thick to see how much this hurts those involved, tell someone else until you tell someone who believes you.
I do suggest you go to the nearest large police dept, be it city, county, state or federal level, and find their sex crimes unit. Tell the people in that unit. THEY will see the seriousness. Just because the cop on the street or at the school doesn't, doesn't mean all cops won't. IF the first group ignores you, go to the next biggest org with a sex crimes or sex crimes against children unit.
You daughter is damaged. She IS disabled and likely unable to not do this. She and society need to be protected from her. The problem is that resources for this are scarce and no one really knows what to do with a girl who sexually abuses other kids. Or really with a boy who does. My son almost ended up with the sexual predator label. NOT because he has a sexual problem, but he learned he could control his sister by making fun of her on the toilet, and of her body. Becoming a sexual predator isn't an all or nothing thing. Ther are levels and steps. Wiz attended a group for sex offenders when he was in the psychiatric hospital at age 12. They described becoming a sexual predator as climbing a ladder. Wiz was playing iwth the first level - making fun of Jess for her sexuality and when on the toilet. LOTS of kids do this at times, but they don't go further and it isn't so much done on purpose as done as they learn how to be a good friend, etc.... (learn we don't tease others, we treat them the way they want to be treated, etc....). The aspergers made Wiz not see things so clearly and act differently than most kids. Jess got upset so Wiz got a payoff, and he did it more often. The group stopped it totally. Actually helped stop a LOT of other stuff that he did to hurt her too.
This group had boys 12-17, mostly under age 15 though. One boy who was a couple years older than Wiz got really really angry when Wiz said something about Jess "earning" or "deserving" some abuse he gave her. The boy was just learning that others have feelings and had just learned that the little sis he abused was hurt by somoene else. He saw himself in how Wiz spoke of Jessie, and he punched Wiz in the face. Hard. The psychiatric hospital staff was NOT happy that I would not press charges. Neither was Wiz, but the kid punching him and then me "taking the kid's side" instead of Wiz' side, made a HUGE impact. Wiz started to see how wrong he was and that was the day he started to make real changes. It was long and bumpy, but it was the road to a positive future for him.
I don't know where your daughter is on that ladder, and others might not use that metaphor to describe how severe her offender behavior is, but that is the analogy that I know for it.
I hope you can get some help in place.
I know we sound like we are catastrophizing and that others don't see it as a big deal right now. Keep pushing to get the help she needs. Don't take no for an answer. Call different law enforcement agencies until you find someone who cares and can/will help you.