I stand to be corrected but in the video didn't the woman ask about Novus Ordo Masses only during the week and elsewhere, that she was well aware of the Traditional Mass? If so, that plainly shows that she was not ignorant of the true Mass.
The 1996 criterion of Msgr. Williamson (which M. Taylor says was also the thinking of Msgr. Lefebvre) is not that one be ignorant of the traditional Messe, but that one is "unaware of, or disbelieving in, that evil, because of the rite’s official promulgation."
From what I recall of that video, this description would certainly have fit the woman.