Brief Answer:
Yes those findings look like the likely cause.

Detailed Answer:
I read your query carefully and I am sorry about what you are going through.

Reading your symptoms carefully I must say that they do coincide with the findings.
The findings (they are from a MRI I suppose) speak of osteophytes at several levels in your cervical spine. Osteophytes are bone spurs which form over the years due to spinal degenerative changes. At times these spurs can compress and irritate the adjacent structures causing symptoms like dizziness neck pain and stiffness radiating in the head and shoulders.
In your case they cause narrowing of the neural foramina, the canals through which the nerve roots leave the spine, which alone or coupled with inflammation of the area can cause nerve root compression. Nerve root compression can cause pain in the arm (although if only the upper arm in your case it might be just radiating from the neck).
Impingement on the spinal cord does could cause bladder issues.

One feature which is not justified though is the excruciating thoracic pain you describe. Also it is not very clear how much of an impingement of the cord there is at C5-C6, the term flattens doesn't make it very clear whether there is significant cord compression to justify the bladder issues.
For this reason I believe a physical neurological exam is necessary if it hasn't already been performed. Compression of the cervical spinal cord should produce some signs on the upper limbs (increased reflexes, abnormal reflexes, spasticity etc). If such signs are found then they confirm cervical spinal cord compression, otherwise considering also your thoracic pain perhaps a MRI of the thoracic spine should be scheduled as well to look for compression at that part of the cord (although it is not as common for the thoracic spine).

As for the treatment of your symptoms in the meanwhile, I would suggest first antiinflammatory painkillers, muscle relaxants, and the use of a soft cervical collar for a week, if not enough medication for neuropathic pain like anticonvulsants (Pregabalin, Gabapentin), or antidepressants (Duloxetin, Amitriptylin) could be added. If compression in the thoracic spine is excluded and the symptoms do not respond to conservative treatment surgery could be considered to remove the osteophytes.

I remain at your disposal for further questions.

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Brief Answer:
Read below.

Detailed Answer:
I am sorry that you are feeling so frustrated. I do believe you have a point, since there already was a herniation in the previous thoracic MRI and it's been 6 years now, it could well be that that has deteriorated and be the cause of your thoracic pain.
It's not the cause of the dizziness, pain and stiffness in the neck though, they are related to the osteophytes as I said. It is not necessary for there to be a herniation, if the osteophytes cause foraminal narrowing, nerve root or spinal cord impingement the effect is the same, little does it matter whether it's a herniated disc or an osteophyte causing the compression.
It is not surprising to have changes through all the spine, that is commonly the case with degenerative changes of the spine.

So since you have changes on several levels all of which could cause bladder symptoms (including the Tarlov cyst) I believe a whole spine MRI is necessary.

You should try to talk to your doctor again, perhaps he might have other reasons for not thinking it necessary. Having the possibility of physically examining you and comparing the findings with the MRI images he has an advantage over me and his/her opinion should take precedence, but they should try to explain you their reasoning.

I hope to have been of help.

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