Zack have you checked, or had your hips checked for unevenness? Sometimes if the shoulders are uneven the hips might be also.

A few yrs ago I noticed my moms shoulders were uneven but she doesn't have TOS or anything like it.
I didn't ever notice my shoulders being uneven until my second shoulder strain injury. And the dr made note of it at one of the appts early on.
My hips are uneven as well. Chiro noticed that & occasionally adjusts as needed.
And my ribcage has been a little bit off since I was a pre teen or maybe longer than that- I only noticed it when I started wearing a 2 pc swimsuit.