The Puebloan culture in the southwest during that time was basically a full fledged civilization. It's insane how underresearched such a culture is despite having built megastructures like within the Grand Chaco Canyon
Nope. Which is what makes it so difficult. Additionally, adjacent nations like the Navajo, Apache, and others are very tight lipped about their extremely robust ancestral and oral history because of bad experiences along with taboos.
It felt like a mix of rightful wariness due to untrustworthy opportunistic anthropologists from the 19th and 20th century along with taboos that developed due to some sort of collapse.