I think maybe this kind of thing happens more often than most of us dream. We've seen rogue employees on YouTube contaminating food, and when I buy fast food, it fairly frequently literally tastes like s--t. It looks okay, it feels okay, but it has that literally s----y taste. It never tastes like that with food I prepare at home, so I have to think that there really is human fecal matter in it. And that it was no accident.
Lately they've found e. coli in cookie dough, which is found in human feces, and salmonella in peanut butter and vegetables. Salmonella is also found in human feces. E. coli and salmonella may also be from animal sources, but with e. coli, they can test and tell what the source is, such as humans, pigs or fowl. Usually the source doesn't make the news, which makes me feel that it has been deliberately withheld.
An acquaintance of mine died from salmonella in her 20s (she had an "underlying medical condition"), leaving young children behind. She was told that salmonella comes from the preparation of food by someone who hasn't washed their hands after going to the bathroom. Her death did not make the news.