I don't have the expertise to evaluate the accuracy of the geographic placements. There was a whole other part of this thread talking about the issue that the map does not pick a single point in time to represent, and therefore there will be anachronisms where different groups shown on the map never lived in the places indicated at the same time (or conceivably never existed as nations at the same time as one another!).

I wouldn't be surprised if the mapmaker had a source indicating that each of those groups had lived in the place indicated during some pre-contact period. But especially without choosing a date for the map, it's tough to say what the "traditional" or "original" location should mean.