Keith, duh, he needs ironing!
I see the same wrinkles on my chubby milks also and assume its from folding. The scales will unwrinkle eventually (or they'd be a wrinkled mess) when the snake shifts position. Is it the cage being too small? No, I see the same wrinkles with smaller snakes housed in a sweater box; they just ball up in a hide or corner and get creases. The less shy snakes rest stretched out in big loops and show no wrinkling.
Oddly, I don't see it on the slender and active youngsters but your point about water is good: be sure the new snake is aware of the water bowl and not cowering in his hide day and night while you rev the Harley in the snake room.
Haven't you seen this effect in chubby Getula? Jeff