What is the name of your state (only U.S. law)? OREGON!

Im posting here for help! To know where to start, actually...
My husband and I are Foster/Adoptive parents, have been since 1996! Loved these children as If they were our own. Three, to be exact. We fostered for a short while, then Adopted! It was just a short while in our Adoption, that our kids began to share their life with their prior Foster Mom. Really sad to hear, that we scheduled an appointment with the Children Protectives Services at our home, only she never came!!! We then got into our car, went to their office!!!
What exactly our kids shared, I can't say here! What the Child Protective Services did, WAS NOTHING!! Infact, after the office visit, a couple days passed, we get a call...saying, "you had better sweep this under the carpet"! Plus, if you know what is good for you, you will...I was so shocked! A day later, I went to their office again, that caseworker had left the building, only to find out she had been PROMOTED!! But, we were left with the thought of loosing these three, if we had spoke out further then! We knew the capabilities of Child Protective Services.
We just got them, fostered for about a yr, then this, their trauma, thier neglect, their abuse and MORE! And Child Protective Services threatened us if we went further with this. Their counseling at the time we went to go pick them up, to bring them home, wasnt going well. A lady at that office, said, "we are aware of what their foster Mom has been doing". Humm, It just didnt strike me then! We were all excited to be together at that moment. About a yr later, we knew more and have learnt the most devasting lately! Our kids are now, Twenty-Eighteen and Seventeen. It hasn't been easy. They have struggled so much, been traumatized, physically abused, and the worst heard here latley! Kept inside two of the youngest ones, till now!
We were never questioned back then on what we knew of their treatment in foster, NEVER HEARD! Neither were these three children. We have reported to several Offices since this. Child Protective Services, the Police(state) and Dr's...Even another Child Protective Services, where we live now! Not even they did one thing, nor questioned the kids either! I was taped, as I told what they had told me, at the State Police Office, while the Child Protective Worker was there! She said nothing to the fact of what I was saying!!
So, what I want now, is to know if there is help! Can we go back on any of this treatment to them? The MALTREATMENT in other words? I can't say here on some of the abuse they had to endure. But, I also NOW know why they shut this up back then!!!! The Foster Mother who had them for around 18 months, in her capacity, is what I mean! Who she was! SHOCKING! Just SHOCKING! That they allowed her to even Foster!
Could someone tell us, if their is HOPE for these Three Children?