Yeah, it's hard to show that the puppy couldn't have escaped on its own. On the other hand, escaping after just less than an hour only having lived there for two days is a little suspecious. I would think that the dog would need time to work out the escape route. Not proof of anything, but I find it a bit sketchy.
The fact that the vet apparently *immediately* brought the dog off to be neutered and de-barked is even sketchier, to me. Especially the de-barking. Why would you de-bark a lost dog you'd only just met? How could he know if the dog had had a barking problem? One hour (at most) with a lost animal doesn't strike me as a good way to get an indication of the dog's usual behavior. The fact that he de-barked the dog suggests that he either is very much against barking dogs and that he let his personal opinions cloud is professional decisions (in which case, he shouldn't be practicing) or that he knew the dog already and had already formed an opinion about the dog's behavior.

I agree that the cases prove nothing significant in the context of the news story. I suspect he's going to get a professional review; I'm sure that any such stories will be heard and considered by more informed individuals in the course of the investigation.

This all makes me this much happier with our vets.