[coronabarb]

With botulism, the spores have to be present first of all, so maybe the potatoes weren't washed sufficiently...or poking the potatoes introduced spores to the interior. The biggest factor was excluding oxygen by wrapping tightly in foil. Then, the undercooked potatoes were kept at too low of a temp, practically room temp, so that allowed the spores to develop toxins. Botulism likes conditions at room temp with moisture, and no oxygen present.