They may even have some suppressed memories or very sad ones they are not wanting to face yet so inside a harmful emotional sore is being opened
For you your seeing validation of your views but for your child your ripping down a wall the child may have built around them to protect them from fears etc experienced a long time ago. Not armed now with the ability to process this information an internal confusion can begin. What harm that may have been caused by the uplift/breakup is now causing an emotional ripple and along its way its including many other issues and emotions the child felt. Your healing yourself but right before you damage is beginning at a far greater level.
Your child may now be much older but these emotions and thoughts are a collection, preserved and held till the child was ready as an adult to discuss and face them or maybe not at all. This faced not in your time but theres. Of course should you just hand your child the collect of legal documents that are often difficult to understand by the best of us yet you having been there in the court room understand them clearly, your now older child does not. These documents you have held may also be a more one sided view and although your selection of papers you may consider right for viewing the fact is the only winner in revisiting this painful past are the bookworms.
You do not have to prove yourself innocent, you do not have to prove someone else wrong... Right now all your child wants is to rebuild the connections with you. When they ask a question keep it simple and take breaks every so often so your not pulled down a road neither of you are ready to process or maybe the chance you may damage a part of your child that can never be repaired, is that a risk your willing to take?