When FDR calls for an end to Ish-ti-opi's ceremonial dance, Eleanor Roosevelt invites everyone to thank Ish-ti-opi in Cherokee. Ish-ti-opi (a.k.a., Wesley L. Robertson) was a Choctaw Indian, not a Cherokee. In any event, the word "yakoke" used for "thank you" is correctly Choctaw, not Cherokee. The Cherokee words for "thank you" are "wado" and "s'gi".
The Navy bandsmen playing during dinner are dressed as officers--bandsmen in the Navy are enlisted sailors. The conductor of the band would have been an officer or warrant officer, but not the bandsmen.
When the King and Queen of England drive through the gates at Hyde Park, and shortly thereafter when they are received by the president, the Marine detail would have been sharply commanded to raise their rifles to the position of "present-arms"--their rifles remain at their sides the entire time.
When Mrs. Roosevelt (FDR's mother) formally greets Queen Elizabeth (when she arrives in the dining room for the formal dinner), Mrs. Roosevelt calls her "Your Highness". She should have called her "Your Majesty", which is the correct title for a the King or Queen.