You post this like it is something new. I've know about Turner's work since 1990, when I had a chance to examine the exact same bones that Turner used in his research. Not by reading an article, or listening to a speech, but firsthand.
Turner makes a leap from pretty tight evidence of cannibalism from those bones to terrorism from Mesoamerica, with little connection in between. It's a neat hypothesis, but it is very hard to test. There is a paucity of evidence of sustained contact between mesoamerica and the american southwest. That doesn't mean there is none or that ideas travel only through material expressions. All it means is there not overwhelming evidence to support Turner's Mesoamerica terrorism idea.
Things may have changed since I did this research 5-6 years ago--I haven't kept up with the research since I moved to a different career.
The Pecos Conference is hardly the "World Series of Archaeology Conferences". It is a place for people to report preliminary findings at the end of a field season, camp, drink beer, and have a great time together (usually out in the middle of nowhere). Turner's work is much more completely described in Turner and Turner (1995).
Archeology has to sometimes make such leaps of connection - as long as you accept that it is a leap and you wil be willing to change your mind when new facts present themselves. I accept the Meso-American explanation for the introduction of a social system that did not exist before or after this period.