I don't like CM and have no doubts the methods he uses while they seems to produce results, can cause more harm than good in some dogs. I'm not saying that CM and especially being left at CM's doggy daycare didn't do more harm than good with this dog. I have certainly seen dogs damaged by poor training, heavy handed training, etc. I know a dog who pretty much flipped out to the point of no return after being left at a chain e-collar trainer's for a month. But it can be hard to say what's what with this story. I suspect it's a bit that the dog naturally didn't have a stellar temperament, combined with heavy handed training, being left for 2 weeks in a daycare setting where e-collars were used and perhaps badly misused, having an owner who doesn't seem to understand the breed, etc, etc, etc.
I absolutely find it believable that in those circumstances an otherwise stable fila puppy would develop major issues. Properly used, I've never heard of an e-collar being used to train dogs under a year old. I don't know if this lady's fila was stable to begin with, but yeah.
And correct filas are not typically dog aggressive. They've got a generous dose of bloodhound in their ancestry and are expected to work well with other dogs. They're one of the very few molossers that tend to be fine with other dogs.