I'm so happy you were able to have the order extended!
Please stick to your convictions about your AH driving your son. Your inlaws are in denial! That is their son and I'm sure they are trying to protect him or feel they are responsible. But that is their grandson and he has his whole life ahead of him and didn't make the decision to get in the car with someone that is impaired. Have you asked your advocate how to get through to them about it all?
Sending you hugs!