Actually, yes. The freedmen in this case were slaves who went to the Cherokees (and other groups, especially Miccosukees and Creeks. I believe some Cherokees owned some purchased slaves, also. The Seminoles took in many escaped slaves and "owned" some of them though it was a pretty relaxed ownership.
As I understand it there were "white" Cherokee and "black" Cherokee back to the early 19th c. Cherokee territory included a lot more than the areas cleared through the Trail of Tears saga. They were the dominent tribe in the original Virginia territories. I have a great ggg grandmother who was Cherokee but she "gasp" assimilated.