Thanks for being so gracious - I haven't experienced first hand how the site works from your side (yet), so perhaps your feedback would be useful to the tech wizards after we are through!
Unfortunately, as much as I wish I could help, I'm not trained with Chinese herbals or eastern/complementary medicine. I've always wanted to do the appropriate training but it actually takes months away from work, which I can't afford at this point in my career :(
One thing that I do use in my practice quite often, though, that I appear not to have mentioned above is laser therapy. Laser therapy consists of treatments done at your vet's office in a series. Laser light is applied to the area and has potent anti-inflammatory and healing effects. I have seen wounds that I never thought would heal improve tremendously with laser therapy. One of my technicians adopted an aged German Shepherd with perianal fistulas a few years ago and we maintained him for a good long time on twice weekly laser therapy and tacrolimus. Laser therapy typically starts with an induction phase of two to three treatments a week until the lesions are looking significantly improved, and then the treatments are spaced out to the least frequent interval that maintains the disease. The brand of laser we use is the Cutting Edge MLS system. Another very popular one is the LiteCure Companion Therapy Laser. There are many other lasers out there, but those are the two I'm most familiar with.
I would also expect that acupuncture could have beneficial effects on perianal fistulas, but unfortunately that's another discipline on my list that I've not yet had a chance to explore! The International Veterinary Acupuncture Society is one of (if not the) most respected certifying bodies for acupuncture vets. I would check their website to help you find a vet in your area that is trained properly. The Holistic Veterinary Medical Association can also help you find a vet in your area with an interest in holistic and complementary medicine:
I'll opt out of your question so that it shows as available to other experts in case any have herbal/traditional Chinese medicinal training :) You can also continue to reply to me if I can clarify anything that I've touched on here.