Can degeneration of cervical spine lead to vad and other serious conditions, death? Fixable? Who and how can fix? How are sublaxations fixed?

Yes. Cervical degeneration can lead to long term problems or severe impairment including paralysis and death if it is accompanied with severe spinal stenosis. A neurosurgeon or orthopedic spine surgeon can assist in your care and help you determine if the condition is serious and requires surgery.
Sublixation can be f. See a neurosurgeon or spine surgeon can realign and fuse sine most serious condition is central canal stenosis causing paralysis rarely.