One of my gripes with Penrose, et al is that he has jumped into speculation about quantum computing in the brain without exhausting more mundane explanations. It seems premature to try to explain consciousness without working your way up from descriptive explanations of "lesser" brains.
I imagine the physics of the brain would be the same for "lesser" brains. With regard to consciousness, in the absence of interactive language (comprehension, decision making and response) - with the "lesser" brains to determine the existence of free will, I'm not sure how else one would proceed.
You're not going to like my response to this, but I don't think free will is exclusive to humans. What makes humans special is not free will, but the ability to "predict" the future, a faculty that is greatly enhanced by language. "Lower" animals have some ability to predict the future -- cats, dog, chimps to varying degrees evaluate their situations and anticipate consequences. But humans can tell stories about actions and consequences, and pass these stories on to future generations. Their range of freedom is greatly enhanced by this. But anticipation is at the heart of whatever we mean by free will. Having one's behavior affected by the future is a pretty amazing thing -- it certainly has the apearance of detaching one from cause and effect -- but it is not exclusively human.