Hello, the 2 of you!!!
I wish you
ALL THE BEST for your Camino.
Just find your own rhythm, don't get stressed by anything or anyone.
I have still some years to work before me, but I already have a hip and knee frailty.
And I did it. So can you!
I just put from Puente la Reina onwards - that is pretty at the beginning - some elastic knee bandages every day without exception, which was really helpful; and when descending hills or mountains, I made pretty short steps.
And I had a walking stick helpful as well especially for descents.
The warm sleeping bags are the right decision, if you cannot sleep because you are cold, how could you manage to do all the Camino.
And as to the Napoleon road : well I absolutely wanted to do it, and I did it. But it was so cold, rainy and FOGGY, I didn't see anything of the landscapes... It was just ridiculous to insist.
So : BLESSINGS, I cross fingers for you, that the doctor will just give some good advice how to be careful with your bones...