ragdoll driver animation - how to save pose when driver is active

I decided to make an crash of some armature using ragdoll physics.
Ragdoll is attached to driver.
Untill the time of crash - driver is zero and pure armature animation is applied.
In the time of crash - ragdoll driver is set to one and armature follows ragdoll animation.
After some time past the crash (when armature stops moving)
I would like to copy the pose in which the armature is left and save it for the next - again pure armature animation.
But because the ragdoll driver is in full power I have no idea how to do this, e.g.
if I add this pose to pose library and after that
if the ragdoll driver is turned off, the pose is changed.