My husband has a story very similar to yours. Found a mass in his neck- turned out to be 2 lymph nodes clustered together. Then we went through figuring out where the primary was. PET scan showed BOT and then he had a laryngoscopy with biopsy on 10/10 that confirmed BOT was primary. This was after months of back and forth with various doctors and we finally went to Cleveland Clinic (#2 in US for Head and Neck) and got an accurate dx and recommendations for treatment. We could have had chemo and rad in Cleveland, which would have been very inconvenient and no family support around for us. It appears the standard treatment for this is Cisplatin and Radiation- which can be done closer to home. So my point is, consider going to Sloan for proper diagnosis and recommendations for treatment and then have treatment carried out closer to home. When my husband looked at what living in a hotel would be like for 7 weeks in a place where we had no family support versus being in his own bed every night with family close by, the choice was easy for him. He is like you in that he feels perfectly fine- no symptoms at all- and the time from when he was first officially diagnosed (10/1) to when treatment will actually being (around first week in November) is very long and stressful- as it feels business as usual. Would never know anything was wrong by looking at him or talking to him but all that is about to change.
Good luck and I am praying for you and your family.