tub (use glass ceramic pyrex if possible, don't forget lid)your infected axolotl in fresh cold water containing 100% holtfreters + 0.2g/l magnesium sulphate, change water daily feed at night change in morning, give daily ten min baths of methylene blue and acriflavine mixed, gently swab infected areas with potassium permanganate.
info for holtfreters here...
Axolotls - Requirements & Water Conditions in Captivity
info for mold treatment here..
https://ambystoma.uky.edu/genetic-stock-center/newsletters/Older_archive/Issues-1-12/archive/Issue 3/09-16brothers.pdf
do a thorough test of the tanks water parameters ie.. temperature, ammonia, nitrites, nitrates, ph, kh, gh.
may be a good idea to use 50% holtfreters + 0.1g/l magnesium sulphate to try to prevent infection of other axolotls, also make sure to clear out any caves/hides regularly to prevent any stagnant areas.
the redness is also a concern may require antibiotics, ensure water is kept cold (ideally close to 15°c/59°f)
although hard to get hold of use Nitrofurazone as directed in the info for mold treatment (under vorticella) if possible.