You never had any MRI at all??
to check for and rule out other issues in all this time?

I kind of had to hint strongly to get my c spine and T spine checked
with the repeated injuries and pain returning after I had recovered and been released back to work - I mentioned we should be sure there is no other causes.

The MRI I had was pretty basic - arms at my sides , hold still etc
{Mainly checked the spinal column - not as a TOS dx thing}

they also did a batch of xrays with me holding 10lbs weights to pull down my shoulders that was rough and some other angles/views.

The MRI machine is very noisy!
clangs, clunks, bangs just be prepared for very loud sounds and they echo inside the tube

You'll probably have to repeat the info about your frozen shoulders to all concerned- I think they don't read the forms we fill out very often.