Prior to the jump he looks like he slips and crossfires a bit... Those kinds of things can be hard to interpret.
I’d hate to dump on a rider without cause... it can be pretty hard to tell definitively what’s going on in just seconds. I’m going to give her the benefit of the doubt, in terms of accusations of abuse or negligence, and hope that the horse can go on to recover.
What is the extent of the injury? She speaks of his career in past tense at the end.
I disagree, there is no doubt she knew something was wrong. Look at the video, at about the 16 second mark on the video, she obviously is looking down, in what looks like an attempt to see what is wrong. She shouldn’t be allowed to get on any horse again. To make a horse take a jump like that when you know or even suspect has a problem is the height of irresponsibility.
Becky