I am not a medical professional and, even if I were, I could not give a specific answer without knowing all the details of the individual in question. I can say that if it were me and I did not have to have immediate surgery to prevent the possible loss of a leg, or part of the leg, I would surely try just about anything to try to prevent losing my toes (but not if the risk was of losing my leg, or part of it instead!).
Since oleander extract was shown to have six times the immune stimulating activity of the most powerful immune stimulators known to man in European studies in 1986-87, I would for sure try it (I take it myself daily anyway) and the other things listed as well. I urge you to seek the advice of a qualified naturopath to get a professional opinion.