I've seen snake scales like this before, but I'm not clear on what causes it either; however, if that was my snake, I'd be dabbing some Betadine just on the
discolored scales. Hope someone else chimes in that has dealt with this. Not sure what causes the scales to "de-laminate", but might be something internal
going on, like an infection of some kind. Wouldn't hurt to see a vet (reptile specialist) & have stool checked too, IMO. Have you ever used any kind of topical
products on the snake before? (oils applied topically can make for scale issues too & don't 'belong' on snakes)