Mark, there is nothing in the Australian Rules of Racing that allows the stewards to relegate a horse from equal 3rd position to 4th that has not been directly involved with any protest - it's as simple as that and your friend the steward may not understood the scenario. Perhaps he or yourself can indicate which breach of the rules of racing a horse (or its jockey) in is in breach of in such circumstances. Stewards do not and can not make their own rules on such issues: they can only follow what the rules state and apply them according to their discretion, but there is no discretion if a horse or its jockey is not in breach of any of the rules as is the case in the original question.