I just watched a youtube about people storing cut avocados with the pits and thinking it would last longer. After 4 days it builds up dangerous levels of bacteria.
Avocadoes have to be eaten the same day they are used.............
I really doubt that is what happened here. Clostridium botulinum is actually pretty hard to grow. There can’t be any oxygen in the environment where it is grown and it needs to be warm. They would have had to seal the avocado in an airtight, oxygen free container and leave it out of the fridge.
I suppose it’s possible but I doubt it.