As the incident was back in 2001 I'll suggest that you don't narrow your search to physios "just" with whiplash as you need someone who knows about broken necks. The problem is chronic and as you say, you have forgotten how to move. The fractures are no longer the main things to consider but long term secondary problems that may have arisen since then. You probably need lots of retraining in movement and I suggest you look for an Alexander Technique Teacher. Look online and you'll find them not too far away. They are more expensive than NHS off course because private but well worth it.
I'm sure as well, that there must be physios in Yorkshire capable of treating you. Have you had NHS or private physio? Were you given a list of exercises to get on with yourself or were you receiving good hands on plus postural advice plus muscle imbalance stuff plus possibly pain treatment if neccessary?
Feel free to get back to me for any quetsions you may have
regards JM