Don't raise the heat, it is already very high for most salamanders, when treating with salt use the short term bath method described in Stotty's link, here, I'll paste it,
Skin Mycosis
Skin fungal infections can occur in contaminated wounds, but are usually occur as a result of very poor husbandry conditions and in very stressed, immune suppressed animals. The skin has tufts of grey or white filaments. Recommended salt concentrations vary widely. I have only had one animal with skin fungus, a mutant axolotl that also had other problems. In addition to treatment, the habitat should be disinfected and remade. A quarantine habitat should be used until treatment is complete. This type of treatment is easiest to use for aquatic animals. Concentrations of salt up to 25 grams/liter have been used for brief treatments. Use the lowest effective salt concentration. Getting a terrestrial salamander to submerge in a salt solution voluntarily can be a big problem.
In a clean bowl mix a hypertonic saline solution. The key feature is a final amount of 6 gm/Liter NaCl (sodium chloride)
Place animal in the hypertonic saline for not more than 30 minutes.
Wearing examination gloves, gently remove fungus
Place in clean normal artifical pond water.
This can be repeated on several successive days, or every other day, for tenacious infections.
Both spanish newts and mudpuppies become vulnerable to infections and fungus at much above 70 F. optimum for them and axotlols (neotenous Ambystoma mexicanum and A. tigrinum) is 60-70 F.
The axotlol is a different but similar looking species, here is a pic
