Goodness that man must have been a charmer extraordinaire!
My late uncle, A.D. Rife, Jr. did a great deal of research on the Rife/Riffe families which he published in a book-for-immediate-family.I will email you his material on Captain Gord.In it he quotes a description given of Capt Gord in 1865 as "Age 22; 6 Feet Tall; Fair Complexion; Blue Eyes; Brown Hair; No Whiskers."
Your rumor seems to have been correct:Capt. Gord was slain with a firearm discharged by Alanzo Jackson during a heated controversy.In the trail, Jackson was cleared of all charges.Capt Gord and his son William Shack are buried in the Davis-Jameson Cemetery-135 in Washington County, Virginia.