POD's way too far back to have any direct impact on North America. Humans only started crossing the land bridge at the earliest 25,000 years ago or thereabouts, and if you accelerate that, it's probably because you're rushing more humans across the rest of the world, too, which only strengthens everywhere else at the same time as the Americas. Part of the issue with North America is that, in the Old World, you had a lot of massive river systems in warm areas where agricultural societies collected and flourished. It's no coincidence that you got early societies in the Tigris-Euphrates, Indus and Nile regions, where the soil was good for farming. Once you get those critical masses of people, they tend to feed on each other. Let's leave aside the idea of innovation; all humans have the capacity to innovate, but greater population density means more capacity for trade and idea-sharing. North America doesn't really have a major river for facilitating a critical population mass at the time humans are showing up; humans there still made huge leaps in things like agricultural practices but the population densities just don't seem to have been as huge. The course of the Mississippi wasn't established until about 12,000 years ago, when the last ice age ended. The Amazon is there for your South America needs, but it's one of the last places humans reach.
You could posit a timeline where settlement patterns are such in the North American south that as the Ice Age wanes and the Mississippi begins to form, hunter-gatherers and nomads in the area migrate to the river and begin farming maize. You could also have the Balsas River down in the Tehuacan Valley attract humans a couple thousand years earlier. Either way, you had maize popping up in the Balsas area about 9,200 years ago; have it spread to the proto-Mississippian civilization and let the river attract a critical mass of peoples using the river to farm maize and fuel the roots of an early sedentary society.
Maybe the earlier start allows them to domesticate some sort of indigenous pack animal, like the shrub-ox, instead of it going extinct 11,000 years ago.