What is looks like to me is brand new hair growing in. That is exactly what Bailey looks like when she molts. She'll get bald spots, and short hair patches. I know it looks cut - you're bunny's hair is like my Bailey's - when the hair is fully grown out it is much flufflier than the tight short (cut look) type of hair that is starting from scratch.
Regarding the poops, because he is ingesting more hair (from normal grooming during a molt), some can get strung together and come out like that in poops. Right now as long as you only saw a couple and the rest of his poops are fine and he's drinking and pooping normally, then just watch. Be sure to groom him (once a day if he's really molting, otherwise a few times a week, until his molting has stopped)
It's important that a bunnies diet is high in fiber to keep the digestive tract moving the hair through. So be sure he's getting enough hay, and is hydrated (wet his greens), and cut back on carbs and sugar treats during this time.
If you start seeing more of the strung together poops, and you see less of the regular ones, and or the regular ones become smaller, then it could become serious, and you would want to call a vet to check him out.
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