You're right, you are on a very heavy protocol and need to help your body detox more. This is a wonderful place to see what kinds of things other Lyme patients recommend/have had success with:
www.tiredoflyme.com/detox-methods.html The goal is to get as many detox pathways in your body working as well as possible.
And by getting the Epsom salt soak water that hot, you are only complicating your detoxing needs as the hot water raises your body temp some and will kill off even more bacteria, which is a good idea, except that your body is already having a tough time keeping up with it's detoxing needs as it is.
Activated charcoal is an excellent way to detox, as it binds to the toxins and ushers them out of the body so they can't be deposited in our soft tissues, organs and elsewhere. The drawback? It will bind to anything - food, nutrients, meds, abx, supplements - so it has to be kept at least 2 hours away from all of those things, plus it can cause a lot of constipation, so it must be taken with at least 8 ounces of water each time. I still use activated charcoal, but sparingly.