Be guided by your doctor, and if needed, they can do a FNAB, Fine Needle Aspirational Biopsy, on the palpable lymph node, even if it's not, with UltraSound Guidance. They do the pathology of the sample taken to show if it's cancer or not, if HPV, and other histology possibly not cancer related, which samples takes 10 minutes to obtain, is relatively painless, in a medical office/hospital, most times with a pathologist, all mine were.

All my office flex scopes, 3, with two separate doctors, showed no sign of cancer in the oropharynx or oral cavity, but did through an FNAB of the lymph node, so they knew I had HNC most likely, and subsequent pandendoscopy, with surgical biopsy, proved positive for small T1 tonsil cancer. Not saying it is, but HPV tonsil/bot may grow faster in the node than in the primary in the oropharynx due to the nutrient rich lymphatics, which also can be microscopic, and not seen visually or by scan or died off at the primary from lack of nutrients when it metastasizes.

A small percentage of patients have an unknown primary that is never found, although the node proves positive, but most eventually are through a PET/CT scan, Ebstein Barr testing, which could indicate nasopharynx, and HPV, in the oropharynx.

Good luck, and hopefully the matter resolves on its own.