I guess you (and others here) have no horse racing experience.
The mirror image is used to decide the order of finish at all race tracks I've been to (and that's more than 30). I've NEVER seen a photo where a horse did not dead-heat with its mirror-image.
And FTR, I have no interest in this race or who finished fourth. I just happened to be watching the races from Kentucky Downs today. To me, this is about the integrity of the photo-finish camera to decide race order.
ML/NJ
I think the display of the video is lagging, but I don’t think it would affect the integrity of it. It doesn’t appear to be a different angle, as there are differences in the positioning of the horses and riders. Take a look at the manes.
Third place horse is also ahead of his mirror image.