Yeah, no, that's an insane claim to make. Obviously American education covers some information about religion in history classes, but that level of detail about catholic history is not normal curriculum for elementary, middle, or high school.
I am not talking about what American education covers nor the average American. But what people with an interest in History, who are reading history books, watching history documentaries, etc. would know. Avignon is not that deep.
Can confirm - I had an excellent, Christian School education through Middle School, and even we didn't hear about that.