My mother's parents, my grandparents were not JW. My JW mother had medical power of attorney and her husband (never JW) was secondary on that. When Grandma needed blood, Mom let her husband sign off. Going back in ancient family history, when my brother was sick with Leukemia in the early 1970's, my JW mother stayed silent about his medical treatment and let my father (never JW) sign off on blood.
So she's always found the loophole to let people get what they need.
It's happened before and it's happening again- apparently, it's time to sign a new medical directive. So she asks me to be second after her (never JW) husband for medical power of attorney (or whatever the specific term is). I agreed. My mother is in generally good health. I can foresee her husband caving in to giving blood to her. If I can see it, I imagine my mother can see it. Then if he's not able, I might honor her wishes. But I might cave in also, depending on the situation.
She said she doesn't want the elders making decisions. My JW wife did ask me a few years ago to sign her card and honor her wishes. Maybe she will also ask me again. I know we argue here whether we should honor their wishes or not and I am not wanting this to turn into such an argument. I mean it when I say I will honor their wishes, but I just may change my mind if I think it will make a difference.