James,
I’m sorry for your troubles. I had a fibula free flap on my right leg for my left jaw about three years ago. Mine was from osteoradionecrosis of the jaw. I was in the hospital 7 days, but was not walking due to prior disabilities, and that they had to take the artery and vein from my chest to supply my jaw as prior surgeries removed everything there. I went to rehab nursing home for three months, and took awhile to start walking again.
By the the time I left the nursing home I was walking. My leg graft still didn’t heal, so I needed another surgery, and graft to close it, which eventually healed. I had no further problems, but I’m not running around or over exerting myself.
I hope this helps!