@kennethb Sounds like your dog just ate his food way too fast hence vomiting up his food.
Is he fixed?
I’m asking cause I worked at a breeder kennel and sometimes when a dog was in heat the male dogs would eat their food whole and puke it back up instantly.
Sometimes the girls would too once in a blue moon. Sometimes when dogs get nervous or feel their food source is threatened to be eaten from someone else they will scarf it.
Eating double the amount he usually eats could have caused indigestion. I personally would have skipped feeding him in the morning. Then go back to his regular feeding at night.
Also look up symptoms of bloat so you can get familiar with the signs and when it’s an emergency.
Yes they did screw you over. Intentionally? Hard to say. More so they didn’t seem to listen to what you were saying and were more focused on “it’s an emergency!” Instead of “he had surgery previous” cause if they listened to you they probably would have caught on that it was staples.
I’d go to the head board of veterinarians and complain about what happened. Just be prepared not being able to use that vet again and maybe search for another vet.