From The CDC:
Historical Review: Megadrought And Megadeath In 16th Century Mexico (Hemorrhagic Fever)
"The epidemic of cocoliztli from 1545 to 1548 killed an estimated 5 million to 15 million people, or up to 80% of the native population of Mexico (Figure 1). In absolute and relative terms the 1545 epidemic was one of the worst demographic catastrophes in human history, approaching even the Black Death of bubonic plague, which killed approximately 25 million in western Europe from 1347 to 1351 or about 50% of the regional population.
"The cocoliztli epidemic from 1576 to 1578 cocoliztli epidemic killed an additional 2 to 2.5 million people, or about 50% of the remaining native population.
The 1491 book uses 94% average for the death rate. I don’t see that in what you list. In calculating it the way the book did, you will get the following results:
Say there were 1,000,000 people (you can pick any number you want and repeat these same calculations) in the new world after the plague. If there was a 94% death rate, the population before he plague would be = 1,000,000 / .06 = 16,666,667 people before.
Using the worst in your post (80%) the population before the plague would be = 1,000,000 / .20 = 5,000,000 or less that 1/3 of the number the book authors were working with. Big difference.
Using 50%, the amount before would be 2,000,000. Even bigger difference.
Also, the book insists that the 94% was the AVERAGE death rate for what is now Canada, US, Mexico, Central America, and South America. That is ridiculous. The larger the amount of land that the epidemic spreads to, the lower the percentage of death. That was shown during the Black Death which has some pretty accurate counts in many places.