Interesting insight on olfaction. Quantum involvement (e.g. selective wave-form collapse) is about the only viable possibility I can see for escaping determinism and allowing free will (and even then we're pushing current physics firmly into pop-sci fiction).
Free will is not something that needs to be saved. We can't save it, we can't change it, we can't create it if it's not there, we can't remove it from the universe if it's there. It exists (or not) in some particular way, and that's it. It would be interesting to find out definitely, but that wouldn't really change anything; and I don't believe if there's anything in our behaviour that should change upon finding it out.