Well, sometimes I feel that if Columbus had not turned up then perhaps Europeans might've been a lot slower in the Americas. With no one to show the world the gold and silver of the Americas, I'm thinking that it might take years to have the Europeans penetrate to the interior of the continent. The Portuguese would have discovered Bahia, and the English quite likely would have found Newfoundland, but neither of those are places that really excite the explorers mind. Further south I can see Tierra Del Fuego found, and the same with the far north as Europeans search for routes around the Americas to Asia, but fairly quickly I imagine they will be attracted by the much richer beds of Asia and Africa.
We will also need to make the Europeans poorer and less interested in exploration. With this we can have at least a native dominated South America (If the Incas can successfully keep things together against the Europeans, not very hard considering the terrain, and we'll need some group occupying Argentina/Chile, perhaps a southern ally of the Europeans in Tierra del Fuego? The Amazon and the Caribbean coast aren't as hard, not much to attract conquerors for a while), and depending on how the Tribes around the East Coast play their cards we might have most of North America free as well, depending on how far the Russians penetrate from Asia. it might be easier to have the Russians be defeated early in the time they move east by someone, to distract them.
So yeah, 1491 POD here. Rambly and a bit implausible but it's there.
Even later, we might be able to achieve something with a weak native dominated Mexico, a victorious Britain in the war of 1812 (A native Confederacy in the Southern Great lakes area would be the point of this, and we might be able to get most of the Louisiana valley under Native control as well, depending on what the British are interested in), and in South America, we might be able to get some kind of Amazonian state, have the natives in the Andes be stronger and we can come, close-ish. With a lot of implausibilities.