For those of you traveling on I-40 in the future, there is a new First American's Museum that opened just a few months ago. We have not yet been there, but plan to go once the "new" wears off and the crowds diminish.
https://famok.org/
And the National Cowboy and Western Heritage museum in on Oklahoma City as well. They have one entire hall dedicated to Native Americans.
Both are highly rated and worth the time to visit.
https://nationalcowboymuseum.org/