I suspect that they die they die. There is a reason Withers is your go to for them. I suspect that you will have to get Withers to bring them back. IIRC weren’t they supposed to be dead already and had a debt to the hells to pay?
That is at least also my impression.
In fact, the entire Withered character feels like someone who can cast Miracle a lot.
"You want to resurrect someone without having the corpse? Well I think that person has a destiny with you, so yes" - *casts Miracle*
"You want some long dead person to aid you in your task with another sword-arm? I guess that makes sense." - *casts Miracle*
"You want to change years of training, because you can no longer overcome your challenges? Unusual, but your task is important.." - *casts Miracle*
All things Withers does, fall in the realm of a Wish or a Miracle.