The horse stunts during the scenes after the accident were done by the real Amberley Snyder on her own horse, the real Power. The ones before the accident were done by her sister.
Amberly appears in season 3 of "Yellowstone" as herself, on horseback at a rodeo, with her story being mentioned by the character Mia played by Eden Brolin.
The actor who plays Tate, Max Ehrich, co-wrote the tie-in song "Ride" for the movie with Snyder.
The character Tate Watkins, is based on a real person (though his name was changed for the movie).