An update that I should have written two years ago. I had a second ultrasound after I had moved back to my home country (three months after the first ultrasound). The lymph nodes hadn’t grown in size and their morphology was normal. Now, 2,5 years later, the lymph nodes are still there and feel the same size. I guess they are permanently enlargened.
I hope you found out something helpful once you got back home.
"Does any of my results sound concerning?"
No, because of the oval shape and normal morphology as seen on the US. I wouldn't spend time worrying about any cancer and ruining your move.
I can't comment on the thyroid nodule.
I would think that the esophageal problem is related to the actual cause of the node enlargement, all of which seems immune related. It can take a long time to get the exact mechanism figured out, so there is no rush. You might have a food sensitivity, as part of the problem. Yes, I'd guess that your teenage experience (mononucleosis?) is related. No, there is no need for another US unless a lot of new nodes pop up, or some new symptoms begin, or any node grows greatly in size.
It is possible that nodes filled in the past with scar tissue (fibrosis) can stay enlarged for many years. Your primary concern should probably be what's occurring in the digestive tract.
Good luck!