Although their intentions are always pure, some dogs can be aggressive or hyperactive and require obedience training. It doesn’t mean there’s anything wrong with the dog, but it’s just to make sure he can be trusted alone in the house and or that he would behave when guests come over (even if he’s not particularly fond of them).
This dog went through the training course and even received a certificate of Dog Obedience Training, but it seems as if it wasn’t much of a training. We don’t think the blame is on the dog here, but on the people running this failure of a program. This doesn’t seem like a dog who’s just been through training, and we don’t think this family would recommend this program to anyone.