A lot of time superworms actually come in oatmeal or oat bran instead of wood shavings or wood bedding like wax worms, mealworms, etc. come in. I occasionally buy superworms from Petco if my bulk online order hasn't shipped yet, and I know for a fact that the brand of superworms that Petco sells in the little round containers come in a dark colored oatmeal. Even if it was wood chips or shavings he ate he'll be fine as long as it wasn't a lot, just watch to make sure he isn't impacted or straining to poop in the next day or two, but chances are that it wasn't actually wood, but rather that dark colored oatmeal or oat bran they usually come in.