Don’t have time to look in detail but one or two things spring to mind. You have a short clivus, that is the bone, to the front of the opening at the bottom of your skull, it’s an anatomical variant. I have it and it didn’t cause me any problems what-so-ever until I suffered a head and neck injury, which caused cranio-cervical instability – then it was a whole different ball-game, with symptoms similar to yours. Have you had such an injury ?
Do your symptoms worsen with your head in flexion ?
You also have a loss of lordosis to the upper cervical vertebrae, so your neck has lost it’s ‘C’ curvature. It would seem that your Atlas (C1 vertebra) is forwards and the posterior arch of it encroaches into the spinal canal. I’d perhaps ask them to check for Cranio-cervical instability, using the Milhorat, Bolognese, Nishikawa, Francomano method, publicised Dec 2007.