Hi and welcome Mickey's mom.
I am sorry that your Mickey is having these problems. I am a big fan of supplements, and some alternatives to conventional veterinary medicine but I have to acknowledge that a dog with an autoimmune disease often needs conventional drugs to significantly suppress the immune system in order to bring the disease under control and into remission.
It is not always necessary to give immunosuppressive doses of prednisolone for some autoimmune skin diseases such as discoid lupus (DLE) and symmetrical lupoid onychodystrophy (SLE,) but if the AI disease is life threatening or it needs to be brought under control quickly such as pemphigus, then immunosuppressive doses of prednsiolone is extremely effective. It does, however, have to be given in the correct dose and for the correct duration to have any lasting effects and to achieve remission. The immunosuppressive protocol that has already been posted by Catherine is the best protocol that I have come across and it can be confidently used as a guide.
It is much better for the poorly dog to put them onto a good drug protocol than to go on for many weeks without achieving remission in an attempt to avoid using immunosuppressive drugs. If Mickey does have an autoimmune disease then it would be better for him to go onto a good protocol with prednsiolone and taper off over a period of a few months than to give something that will not fully address the problem, and the immune destruction of the skin, that is causing ulceration, will just continue and get worse.
If you wanted to avoid the use of steroids then you might try a treatment of doxycycline and niacinamide with the addition of Natural Vitamin E and essential fatty acids. This treatment could take 9 months or more but it may work, depending on the sort of autoimmune skin problem that he has. Even if you go down the steroid route you might consider adding EFA's, because this does have an anti-inflammatory effect after a while, and is known to be 'steroid sparing', and Natural Vitamin E as this encourages new cell growth, but it has to be the natural form because the synthetic form is not effective.
Have a chat with your vet and don't be put off by using conventional drugs, but be sure that it is the correct dosage and the protocol is a good one.
Jo