I know this is Pacman - but your Nonsense-Nahua has some Semantic Meaning.
And there's no such thing as Forbidden Codices - The Aztec were pretty open about the Apocalypse and all their Murderous Gods.
It was not the Spanish themselves - It was two priests.
One - De Landa, feared what he saw and condemned it to the inferno.
The Other - Sahagun, understood that what He beheld was the work of Millennia of Human Culture.
Nahuatl was preserved - and Maya was Lost.
But What's left amazes to those who can grasp it.