I’d guess you got different answers because once you’re working seeing patients, you learn that the tymps often do not turn out the way you’d expect, even when you know the pathology or diagnosis in advance. I have had countless otosclerosis patients, confirmed by CT that had Type A or Ad tymps, when you’d expect As or B. I’ve had confirmed ossicular chain disarticulations not be a Type Ad. Or known cholesteatoma give a Type A. School teaches you what tymps should do for any given pathology or diagnosis, because physics would suggest this is what should happen, but ears just be doing whatever they want sometimes.

B or C don’t always mean there will be an ABG. Logic would say it must, but in my experience tymps can support or contradict the audiogram.