Yes, it is so possible for an animal to bond with a human. We see this time and time again. There are very strong bonds between people and animals, not just with dogs and cats but with all types of animals. Look at sanctuaries and you'll see beautiful bonds between people and elephants, lions, cows, penguins, and more.
It puzzles me that this is considered to be a breakthrough, although the information does come from a new study. Oxytocin is simply a "feel-good" hormone, part of the brain's reward system. Animals learn to feel safe with "their" humans, in the same way a child does with its mother, or father for that matter. In both instances, this feeling of safety has to do with being provided for, including being fed. Therefore, if a dog is able to recognize its owner the same way a baby recognizes its parent, it makes sense that the animal's brain will release the same hormones that a human's does.
Yes, it is possible for an animal to bond with a human. It happens all the time. They're called pets. Humans have always shared a bond with animals and it has been shown to improve health for both the human and the animals. How often do we see news stories where an animal has fiercely protected their human owner and even sought help for them?
When a dog moves to a new home, the dog is happy with its new owner quickly. A human can likely bond with the animal, but the animal doesn't have the same reasoning skills as the human has. The animal just wants to have its needs met, so it can have food and water.