There was a lot about that race that was strange. DRF has an article about it. I couldn't see that there was any contact between the 12 and any horse. The horse to his inside steadied, but I think that was more to do with the horse to his inside(the 7?) being pushed into him by the 1. According to the article, Castellano, the rider of the 7 lodged a complaint against the 1, but that was not relayed to the stewards, but strangely, the inquiry sign was next to the one and no other horse.
Must admit I am no great observer of what goes on in races, but I think you could make a case for the 1 coming down and that seemed to be what the article in DRF was saying.