Oh, alright. But only because you said please and thank you!
The file I've attached will override the Brotherhood Headbutt finisher with the Backbreaker finisher.
This will apply to all characters throughout the game who use the Brotherhood melee style.
Replacing melee animations can get a little more complicated, because of there being two animations for each finisher (Attacker and Victim), and each of those having impact triggers which might not align correctly with a different animation. And then there are other triggers like Camera Angles, and different amounts of Damage infliction, etc..