newengland,
I am so glad you found us, welcome to Sober Recovery.
IMO, I would just concentrate on your beautiful grand daughter, and let your worries about you daughter go by the wayside. Unfortunately, it doesn't sound like she is going to pass a follicle test any time soon.
And, if you have legal custody, this will be not decided by you, it will be decided by the courts.
I know it's hard, but try the one day at a time.
Hugs...