No problem, glad to be of help, just wish I’d more time and energy to dedicate to it!
The only real thing a diagnosis can do, is make you more informed about the nature of your condition, thus making you more knowledgable about how best to manage it (know thine enemy!)
If it is craniocervical instability (CCI) then it is CRUCIAL that you restrict any action that is going to apply subtle pressure on your brain and brainstem – or your future could be very bleak! The trouble is, unlike any other area in your body, if you are subtly damaging your brain/brainstem, you feel no sudden pain at the time, just maybe enhanced dysfunction symptoms (i.e. tachycardia, or numbness/tingling, or lots of other things) at the time, or at a later time. In my book, it’s in your best interests to treat it as such – until proven otherwise, that way you have everything to gain and nothing to lose. If you suspect it, in my experience a Philadelphia collar is best, as a soft collar does not support the head sufficiently and can be worse than not wearing anything.
For anyone interested in The Chiari Institute method, that’s the Bolognese/Milhorat/Francomano method for determining craniocervical instability, which I mentioned earlier, here’s the paper: