She's a beautiful little girl. With her losing motor functions, it does look like a stroke. Does she have more difficulty using one side more than the other? I know she was flopping around, but does she switch sides or is it constantly one side that is limp?
If it is a stroke, she will never make a good breeder. She will probably not make it through it this time and they almost always stroke out again, and breeding only increases these odds. If she lives, I suggest making her into a cage mate for other pregnant females, etc. Breeding her would likely cause her demise.
Honestly, imo, no matter what, she is not good breeding stock and I would possibly consider the new bloodline one you don't want to incorporate into your lines. Unless you know the bloodlines and this is a new health concern.