After I inserted one video into Track 3, I revealed its audio in Tracks 4,5 and 6.
I left my second video unchanged, which is inserted in Track 7. I seem to prefer not seeing the audio tracks but I don't know how to reverse what I did to the first video.
OK. I think I solved this one on my own. Not sure how I ended up with extra audio Tracks for one video. I rt clicked and deleted audio object. Then I rt clicked again and restored audio object. Then I rt clicked again and made the audio a separate Track, therefore giving me the proper "one" audio track. Whew! Now I can easily select one for the Master audio track for Multicam.