Well... as certain as I've found anything to be in this area, I found this in Woodward:
In letter June 16th, 1858 to COL. JOHN BANKS:
The boy that was with Mrs. Brown, was the son of James Harrison, who was a man of great daring and had suffered much from the Indians, and they in return had suffered much from him. He was the man who killed the father of the present speaker of the Creeks, Hopothleyoholo, and was known to the Indians as Epha Tustanugga, or Dog Warrior, and to the whites as Davy or David Cornels. Davy Cornels, I suspect, was the cause of more mischief done to the whites by the Creek Indians than any man that ever lived in the nation. He was troublesome during the Revolution and long after. While Seagroves was agent, Cornels sent him word that he wished to be at peace, and would meet him at Colerain, not a great way from St. Mary's. Seagroves unfortunately let it be known that he was expecting a visit from Cornels. Harrison heard of it, collected a few men, and I suspect Brown's father among the rest. All had suffered long and much from the depredations of Cornels and his men; they knew his path; they watched it closely, and one day as he approached them with a white flag, Harrison killed him. So ended the life of the most bitter enemy the whites ever had among the Creek Indians, Sowanoka Jack excepted.
So, James Harrison killed Davy Cornels (AKA Epha Tustanugga or Dog Warrior), who was the father of the speaker Hopothleyoholo. In the US G'ment papers of the time (online) there are lots of accounts of Davy's murder as well.
I don't know of anything to support your other two possibilities.