Some Muskogean speakers also settled among the Cherokee, which explains some of the place names you mention. For instance, I understand there was a “Taskigi” town among the Cherokees as well as among the Creeks. The name is Muskogean, with the root “taska” meaning “warrior.” Taskigi is the origin of the name of Tuskegee, Alabama, and Tuskegee University.

Some of the claims for Creek/Muskogee origins of place names in Cherokee country should be treated skeptically, however. Just because place names look similar when transcribed by English speakers, that doesn’t mean they have a common origin. “Chattahoochee” and “Chattanooga,” for instance, seem very similar in English, but their origins are Muskogee and Cherokee, respectively — two very different languages. So I would be skeptical of giving, e.g., “Tallulah” a Muskogean origin just because it begins with “Tall-” like many Muskogean place names.

Place names in the South are full of surprises. Some names that seem “Indian” (e.g. Tallahatta Springs in Alabama) were made up by whites, while others that seem “Anglo” turn out to have Indian origins (e.g., Capshaw, Alabama, a garbled Chickasaw place name).