The bacterium can germinate in a beneficial environment with good growth conditions. If it germinates out of the spore in the stomach it may be able pass to the intestines (unclear). Or it may remain dormant and become active past the stomach.

Per the CDC -"Adult intestinal toxemia (also known as adult intestinal colonization) botulism is a very rare kind of botulism that can happen if the spores of the bacteria get into an adult’s intestines, grow, and produce the toxin (similar to infant botulism). Although we don’t know why people get this kind of botulism, people who have serious health conditions that affect the gut may be more likely to get sick."

I was trying to provide info of the bacteria in general as it pertains to infants and their digestive system and what pH conditions it can/cant grow in, so I thought it was helpful to look at the pH environment of the stomach too. Since we don't know exactly how adults get intestinal botulism I threw it in as additional info. Also, a lot of people don't know about botulinum spores and how pH plays a role so I thought I'd share.