It cannot opportunistically morph between a human for benefits and a machine for liability.
Indeed. Though here it would be morphing between human and machine even just for pure liability, which is even worse.
We have no way to tell if a machine has an experience (in general and not only) when being positively or negatively rewarded for what it produces; even if we assume it does, we have no way to tell if punishments are experienced like mild scolding (and rewards like mild praise), or if the punishments feel like being burned to death at the stake (while rewards feel like a religious experience combined with an orgasm).
We are just beginning to scratch the surface of what these kinds of question even look like in mechanistic terms; all philosophical discussions before it about p-zombies and the Chinese room and so on, they are all no more useful than any other non-expert armchair experts discussing things.
Even the current research, such as it is, is probably only at the level analogous to humoral theory when we want something at the level of germ theory.
The liability lies with the owner and the punishment(monetary or other) should strongly incentivize the owner to reduce the incidence of bites.
> If a dog bites, we don't wait to take action until we figure out a way of teaching the dog the experience of guilt or punishment.
When we invented the concept of legal liability, our species was broadly still animistic and panpsychic. The concept of a "scapegoat" is named after the idea of literally putting the sins of a village into a goat and driving it away.
After doing that for perhaps 4500 years, we are now in the position to do as you say for e.g. dogs (and also machines).