dear sadman - welcome to SR. i'm sorry i didn't get a chance to reply until now. your story and the situation is sad, tragic and scary.
i understand the resistance to getting CPS involved - but you have babies going on drug deals. most of us remember this story:
https://www.independent.co.uk/news/w...-a7307391.html
since you have GPS on her car, you could always call 911 and report a suspected driver under the influence. you could call and speak with social services/CPS without committing and ask them what steps they would take. you could repossess her car.
i hope you find a solution soon. again, so sorry you have to deal with us. prayers for you and those babies.