The only cure I ever found was when I waded through a stagnant pool to get access to a caravan site in South Wales. Not sure what was in the water, but my feet had lovely skin for months after.
Not exactly a cure as it only temporarily removes the flaky bits, but the dog loves licking between my toes when they’re particularly encrusted and to be honest, it does feel quite nice in a pain/pleasure sort of way – especially when she has a quick nibble…
Hope that is of help to you.