I worked on the BLM programs in Santa Fe and Canon City 20 years ago. I submitted a treatment and script about my experiences to Sundance soon after, though my story was based on the ex-rodeo rider running the program. No reply.
I'd also written an article about the Canon City program for The Sunday Telegraph in the UK. I have a collection of pics taken then by a professional photographer.
I haven't seen The Mustang, but from the clips I have seen there are no mustangs in it, so from a horseman's perspective it's probably rubbish. I'm not sure if I can bear to see it. One thing that does ring true is the ketamine connection, although there was none in the drugs cabinet in the tack room. If ever we needed any it was brought in by the vet.