I've stopped counting NF in these kinds of situations. There are so many things like that that I've started thinking of NF taking place in a separate universe that is very similar to the one in the novelverse.
There's a TV trope for this called, "Broad Strokes" where there's a bunch of stuff in something that is important and should be considered canonical but not every detail is. Which I think fits NF to a t.
In my headcanon, Mac Calhoun and his adventures occur but this is all some bar-story and only the rough events occur with a lot heavily exaggerated.
Others may view NF as absolutely canon and everyone else who makes the mistakes.