This is just my mom observation on almost all "I'm going to do it my way" people.
They tend not to respect authority and can't be told what to do, even by the police. It doesn't make them bad people, although their actions hurt us...we are not the purpose of their behavior.
Okie, you have been a champion, bursting with love, for this child. You have done even more than most parents do. You are a hero. Maybe a tired hero, but a hero anyway.
He is safe now. Please be kind to yourself. It's hard. I know. Me too. All of us. But you know that for now, your son is safe and able to utilize services to help himself.
Hugs and love
. Prayers too.