As long as you don't pretend they're actual facts it's all good. When you try to muddy the line between history and fantasy it's another story. fyi their slogan is "History awaits you" ...
I think your outsized negative reaction is due to the fact that Puy du Fou does a better job popularizing history than your average French history teacher.
That they take a slightly different view at historical events is ever more outrageous, but it only shows how one-sided and politicized history education is in France.
FYI, I am an outsider not really interested in French politics, just happened to leave in a nearby country.
I can guarantee you, it is not. This is 100% about what you just said and 0% about French history teachers, of whom I've met none, or Puy du Fou, which I had never heard of before these posts.
It may be conductive to have some legends even if that stuff doesn't fly with your history teacher.