My first thought was colloidal silver. It's anti-bacterial, anti-viral and I think anti-fungal. I'm not sure how much to give a GP, but that was my first thought. It can be added to his food and/or used topically.
2nd thought was a detox, which you mentioned. If she does that, he may need liver support, which can be provided with milk thistle.
There are holistic vets out there that do phone consults, and I thought there was one in NJ who can also provide the homeopathic nosode for rabies (lyssin). Unfortunately I can't remember his name, nor can I find him via the AHVMA. But if you want to pass the link for AHVMA to her, she can try to find someone on there who does phone consults and homeopathy.
http://www.ahvma.org/ I did find one in Massachusetts who does phone consults (warning, these vets and consults are NOT cheap):
http://www.homeovet.net/content/client.html I make no promises as to how good he is or if it'll work. But I truly understand the desperation.
Here's another one, but I didn't see if they do consults, and I would recommend working with a holistic vet if she uses the lyssin:
http://peterdobias.com/products/lyssin-200cCoconut oil might be a good idea if used topically on the infected area. It's anti-bacterial, and it also moisturizes.
He should also be on a good probiotic, if she's not doing that already, because the antibiotics have probably wiped out most if not all of the good bacteria in his intestines. That's a huge part of his immune system, and it needs to be built up again. (Colloidal silver doesn't kill good bacteria.) Colostrum would also help his immune system.
And this may go without saying, but she needs to remove any grains from his diet. Those are not helping, and the sugar (carbs converted to sugar in the body) may be feeding the bacteria and contributing to the inflammation. The body uses protein to make blood cells, including the white blood cells used to fight infection.
Vitamin C is anti-inflammatory and also supports the immune system. Some good omega 3's (e.g. krill oil or a good quality salmon oil) are also anti-inflammatory and may help the skin heal. I'm tempted to suggest vitamin E (good for the skin) but it's a fat-soluble vitamin and if I remember correctly, can be toxic in high doses. There are cream versions that can be used topically, but I would talk to the holistic vet first to make sure it's ok to use.
I've run out of steam for the moment, but if I think of anything else, I'll be sure to add it.
to you, your hairdresser and her furkid!