In G.I. Joe: Renegades, Flint is First Lieutenant Dashiell Faireborn. He was officially tasked to arrest the Springfield Four and personally opposed to the Renegades' actions against Cobra. A talented officer himself, his greatest failure (and best deed) is using Lady Jaye as his assistant on his mission without awareness that she is actually supporting Duke against orders and against Flint. Despite being oblivious at best, Flint is fully aware of Jaye's sympathy to Duke and retains her in this position, believing this would make her more willing to bring him in safely.
In a flashback as seen in the two-part episode "Homecoming", teenaged Flint was a football player who led his team to victory with a play that ended up breaking Duke's leg. Flint was happy to rub this in until he realized how serious the damage had been and that this ruined Duke's chance to get a football scholarship to college. To help him out, Flint got him a job in the army. In a later encounter, he pushed to get the fellow officer a medal after seeing Duke save another soldier's life. Despite his overbearing and arrogant manner, Flint in "Homecoming (Part II)" claims that he is Duke's friend and has only ever tried to help him.
While Flint remains antagonistic to Joes, he's still shown to be one of the good guys: Flint launched a raid on a corrupt prison; distrust of and distaste for Baroness' Cobra troopers. When the Renegades are briefly in custody, Flint interrogates Duke: he doesn't believe the truth about Cobra Industries but as he knows Duke is a good man, Flint believes he was coerced into destroying a Cobra factory on behalf of unknown backers who will now want to silence him. Because of this belief, Flint arranged the Renegades' families under armed protection, which didn't go unnoticed. When the Baroness attacks the prison transport train, he reluctantly recruits the Joes to fight her off; when they escape afterwards, he deliberately doesn't shoot Duke when he has a clear shot.