The man listed as "mulatto" may well have been the man mentioned here. Teamster is a more likely occupation for him than a combat role, I would think, so again that could well be him. I presume he was a free man if he was able to volunteer for service in the army.
My 4th great grandfathers sister was a "mulatto". Her name was Mildred Gaines. Her brother John P Gaines Governor of the state Oregon his other brother HK Gaines wanted to marry Margeret Garner. The slave woman who killed her children so they wouldn't be sold into slavery even though they where already freed. My family actually freed all there slaves. Where not in slaved states.