Does child services have the right after all charges were dropped 5 years ago?

This may seem like an odd situation but I assure you, it's true. When my daughter was 7 ( she's 12 now ) her birth mother convinced her to tell a teacher that her step mothers brother had touched her, she gave her details on what to say. He was arrested, all of his laptops were confiscated and searched, she was seen by medical professionals and counselors that were approved by the court. After finally realizing why she wasn't seeing her uncle anymore, she felt bad and told the truth, that nothing had happened. We contacted the detective investigating who said he had found absolutely nothing incriminating on his laptop, the doctors who examined her, reported that their were no signs of any physical contact to show that she was ever touched in any way. She admitted to her counsel about what her mom had her say and all these people ( detective, doctor and counselor ) recommended that all charges be dropped, and the courts agreed and so they were.
Okay now the issue and the question.
It's five almost six years later and somebody made one of those cowardly anonymous child services calls because they felt she was neglected because her pants had a hole by the knee. The child services lady after her walk through of our home and determined that there was nothing wrong and the kids were well taken care of. Then before she left, she decided to tell us that my kid's uncle is not allowed around them and if he is, she will remove them from our home. That was NEVER a stipulation set by the courts and when I pointed that out to her she said these exact words. " It doesn't matter what any of them said, we have insurmountable evidence that proves he is guilty of all charges. " I asked what proof but she would not tell me, she just gave the threat again.
Here are my questions, does she have that right, to make that demand of us? And if they really had all this insurmountable evidence, why would they have agreed to release him?
This has thrown our family into a turmoil and the kids are devastated and we are living in fear of losing the kids. Any advice would be great. Thank you.