A story found in the Memoir of Jean Baptiste Faribault.......
"One Crawford, a brother of the agent heretofore mentioned, took up the quarrel of the Company against Campbell, and challenged him to mortal combat. ...Campbell accepted the challenge, and the parties with their respective friends, proceeded to Mackinac
Mackinac Island In The Distance
and thence to a small island at the mouth of the river St. Mary's, near Drummond's Island, where the duel took place. Campbell was shot dead at the first fire, and Crawford was slightly wounded. The descendants of the two combatants do not seem to have continued the feud, inasmuch as Mr. Crawford's grandson, LaChapelle, is married to Mr. Campbell's granddaughter... ."
This incident was also mentioned here:
Faribault's...last act for the company was the delivery to Mackinac of his fur returns, whereupon he heard of the August 11, 1808, death of his friend Archibald Campbell at the hands of Redford Crawford, brother of Louis, in a pistol duel at Drummond Island.
This source says it was John Campbell who was killed in the duel at the hands of Louis Crawford.
And this source:
(I)-John Archibald Campbell (1775-1808), who became U.S. Indian Sub-Agent at Prairie du Chien, is killed in a duel with trader Redford Crawford; Campbell's former trading associate. (I)-Robert Dickson (1768-1823) was acting as Redford's second. John left seven Metis children to fend for themselves as his Dakota wife died in 1801.