Sherman Sage, (aka. Old Man Sage, Good-To-Look-At, Well-Knowing-One, and possibly Green Grass) (Arapaho) from an interview with David Humphreys Miller in 1939, with my annotations in brackets:
Mitch Bouyer [ie. Mitch Boyer] may also have been killed down by the river toward the end of the battle. Sherman Sage, Arapaho warrior in the fight, told me in 1939 that a man in a calfskin vest and a soldier with a bugle and a carbine escaped from the [Battle] ridge and got down to the river [note: likely at Ford C at the mouth of Deep Ravine], reaching the west bank before the Sioux and Cheyennes found them. Bouyer, it was said, begged the Indians to kill him, which they eventually did. His [ie. Boyer's] body was thrown into the river along with that of the bugler. [Note: Hollow Horn Eagle and Brave Bird and Hollow Horn Eagle both told of a Seventh Cavalry trooper was killed at the river after the battle.] The story rings true, for the Arikara scouts knew Bouyer as Man-with-a-Calfskin-Vest rather than as Two Bodies, and it is probable he was wearing such a garment the day of the fight.