I don’t know what happened to their dog, but the story about the car is BS. Bleach in a gas tank would likely cause a little damage to a car’s fuel system, but it is heavier than gasoline and so it would sink to the bottom of the tank displacing the fuel. The car would stop running almost as soon as it was started up. Adding bleach to the crankcase would cause damage to the bearings fairly quickly, but adding water or antifreeze to the crankcase would do the same type of damage and a mechanic would assume that a gasket had blown so most likely no one would figure out what had happened.
But the person said, “I smelled the inside of my gas tank and there was bleach.” I didn’t know you could get into your gas tank.
Don’t most new cars have locks on the gas cap? Even on my 2001, the little door would have to be pried open and there would be visible damage.
Fuel filters prior to gasahol would completely block water. As to bleach in water passing through with 10% alcohol??? What ever happened to moth balls or sugar in the gas?