Correct, Jenny, to the ultimate !In the past it was common for owners to use a pseudonym; notable examples were both the Prince of Wales and his mistress Lily Langtry, but there was nothing improper in it. The race was truly run, which is why no owner, trainer or jockey had made an objection before the racecourse stewards and why the judge had flagged it as a true run at the finish.
The disqualification , from the stewards themselves of their own motion, using the pretext of obstruction, was not announced until half an hour after the finish. By this time the pseudonym had been found to be that of the owner 'B.Ismay'. Bruce Ismay was generally believed a coward who had acted disgracefully during the sinking , abandoning the bridge, where had been lording it with the captain, and jumping into the last boat. Sadly for the true owner the other B. Ismay (Bowyer Ismay), not Bruce, but of the family, the stewards must have presumed they were disqualifyinng the scoundrel's colt. By the time the correct Ismay had found out he was out of time to lodge an appeal to the Jockey Club.
Racing people had had the Derby to beat all Derbys; a suffragette, Emily Wilding Davison, killing herself under the King's horse, Anmer, a disqualification, and the longest price winner to the time at 100 to 1 ! As a bonus not only did bookmakers pay out on the wrong colt (at one and a half to one; 6 to 4 ) but two colts in the placings were mistakenly reversed in the confusion.
As a footnote: Queen Alexandra sent a telegram of sympathy after the woman was fatally wounded under the hooves of the King's colt. She sent it to the
jockey Herbert Jones, who was bruised in the fall ! She complains of 'this lunatic woman'.

[ My family really must be sick

. Mrs FP has the telegram and also the Suffragette scarf that poor Emily was wearing at the time

. The scarf is in the Suffragette colours of Violet Fern and White for Votes for Women. There were no bloodstains just tears from the hooves ( see, we are not
that sick !) Emily died days later from internal injuries , having been attended at the scene by her own cousin, a doctor, there by chance and unaware of her presence at the meeting. It was he who kept the scarf. ]