This was painful to read. Why were you, "Embarrassed and chastised, I could barely look my boss in the eye."? The assistant principal simply worked out a compromise for you to do your job.

As a teacher, I can confirm that this kind of thing happens, whether or not this story is true. I've had parents complain about not knowing anything even though agendas had been marked for months. They've never checked online grades but then react with surprise, if they care at all, that little Jose is failing. Our online system even lists the grade for each assignment the instant I input it.
However, any principal I've worked with also knows this about the parents, so they put on a show to calm the animals down but trust you to do something to try shutting them up next time.

Basically, parenting and educashun(!) system are going hand in hand, down the drain, leaving behind a generation devoid of any real life skills

Graduate high school at 18. Graduate BS at 22. Graduate MS at 24. This happened to a 21 year old middle school teacher. I call Shenanigans