Hello!
Yes, it has been a long time since I wrote about my concern about the persistent swelling of my left supraclavicular. Mostly because I am still without a diagnosis. At this point, I have been referred to Internal Medicine and awaiting appointment.
It is nice to hear from someone who is experiencing the same and I wish you luck on your search for help.
Below is a list of tests that I have undergone in the past year and the results, starting with the most recent.

CT neck (supraclavicular) scan, which was considered an unremarkable examination. In particular, there was no lesion, no neck mass or lymphadenopathy and no abnormal or prominent vessels to explain the swelling.

Chest X-Ray which also was unremarkable.

Vascular ultrasound of the Left arm/neck/aorta region, which indicated there was no blood vessels/artery dilation causing the swelling.

Soft Tissue(supraclavicular) Ultrasound, unremarkable.

Take care,
Tully