Sorry you are having so much trouble with RSD. I have PN or RSD in left ankle, however not as extreme as what you are describing.
I do not know if there are other answers, but I would seek Mayo clinic or some diagnostic center, before I would ever consider having my foot and ankle amputated. There has to be someone in the country that can help you. I hope that some other folks here can guide you to a better solution. Have you tried Katemine? Infusions, and or cream? I have heard of this being done before. Keep posting, you will get a response soon. Hang in there. ginnie