There was one individual who was known to be unfair, and an ********* in orals and had a high failure rate. But to be fair, the guys I know failed it were either unprepared, or just weren't going to make it anyway. I hear this individual is no longer doing orals, but I can't confirm that. YOU need to study and put in the work. If you don't, that's on you.
Airline training is tough, and people who don't know or haven't been though it before can easily get behind and overwhelmed.