I'm sorry you are anxious Garden Mama. I can relate totally. As much as I would like to know my son was seeking recovery...I don't think I want him on my doorstep. Or the chaos that subsequently follows him. You've researched some options for them...how they respond to that will be a good indicator of how serious they are. Are there any Oxford houses in your area? If people are serious about recovery they can also be a good support and option.
I'll be sending extra prayers your way. As Kindeyes has always said...parenting is not for weenies. Big hug being sent to you.