The fungal infection my grandson had was not the same type of fungus as candida. There are many different types of fungi, some cause symptoms in humans, many do not. My grandson's patches cleared up after about a week of treatment, and after some sun exposure, (gradual, not sunburn), his skin pigment returned to normal.
As a rule (for myself), when treating anything in myself or my family, I always look for the simplest most likely cause of a set of symtoms, first. 9 times out of 10 the simplest solution is the correct one. If the condition doesn't clear up after treatment, you can always have a further investigation.