To ask for advice

[Anonymous555]

Some background: had an 18 month relationship 12 years ago. Realised he had a lot of issues, ended it, found out I was pregnant.
Kept as much distance as possible through pregnancy, but allowed him at scans etc. Beautiful DC arrived, father was in another relationship by then. Met her, felt OK with him having DC 6 hours a week. DC always came home crying, was scared to go with them anyway. 2 years later, she has a DC of their own. Father of my DC decides to walk away from them as new partner hates that my DC exists.
I was relieved, waved him off. However, DC is now 10. Severely autistic with other possible issues. His 'father' said he'd sign away his parental rights, then moved. I can't find him. Council refuse to assign him a 'special school' (I know that's incorrect wording but can't think of the right words) without everyone with parental responsibility signing the form. Wtf am I supposed to do??

I would say see a solicitor

My solicitor drew up the papers. No good if he can't be found

You need proper legal advice. Other school things, medical issues etc tend to only require one parent to sign things unless the other one is actively objecting. I wonder if your council is trying to find you off...
Your child has rights in their own right (iyswim) too regarding their education.
Good luck!

Have your solicitor sue the school? Could a techy genius maybe track him or this other woman down?

I think the solicitor can put notices in the paper seeking him particularly in the area where he was last known, seeking him. That's how it was done years ago. As long As it is shown that you tried to find him. If unsuccessful then solicitor can apply for you to be able to sign on your own. This might not be quite accurate but it's how it used to be done.