I sympathise OP. When the state comes a calling uninvited, it's unnerving and when the state colludes with it's minions in institutional gas-lighting it can get really out of hand, so I'm really glad the SW was reasonable.
I've read the whole thread, and many others over the years, and the positions are always somewhat polarised between those who have been chewed up and spat out by the system, and those who are fortunate enough not to have been. Of course there is a bit of a middle ground where the state has actually provided the help it is mandated to, and despite bureaucratic bollocks more good than harm has been achieved, but due to the secrecy around child protection matters we will likely never knowexactly the scale of disasters going on and families being wrecked.
Before you go "but but but" and talk about how child abusers exist blah blah blah, be aware that there are a significant number of people going through the system who are well aware of that, and have to deal with the cognitive dissonance of knowing they are not child abusers but being expected to have their children used as carrot and stick by various professionals and be grateful for it "just in case" and to deter others.
Being accused of child abuse and having to go through the family courts is the worst kind of psychological torture imaginable if you are not guilty of what you have been accused of. The standard of "proof" is balance of probabilities not beyond reasonable doubt. Expert opinion wins the day. See where that got the Websters, Sally Clarke (may she rest in peace because that was an absolute shocker of a case), Angela Cannings etc.
And that's the thing - you may be "guilty" in the family court and permanently lose your child, but you may never be prosecuted, so you can't have a stab at proving your innocence in criminal court. That's if you can even get expert witnesses to testify in your favour, as those who challenge the orthodoxy of medical dogmas surrounding child abuse are struck off and the pool is now almost empty in the UK.
Look up metaphyseal fractures - that's a good starting point if you don't believe that the system, once in action is a juggernaut that can't be stopped.
Of course one should co-operate with people who claim to be there to support families and protect children, but the lovely naivety if "nothing to hide, nothing to fear" can soon be destroyed when professionals with power are telling you you're an abuser when you know you're not, and no amount of co-operation makes a difference.
Just accept that some people do get a very rough ride through the system, not all professionals are above preserving career and reputation at all costs, and there are some who do enjoy the power. If you haven't been there, I'm glad for you, and hope you never have to. If you have been there - solidarity.