The moment that Duke Ersi Ester won the wolf transformation form skill page, his rival guests and their supporters left without even saying a single word. Fortunately, the unexpected event concerning the vampires was completely disregarded by everyone as the majority of them thought that it was all a part of an act to increase the value of the main item.
That said, Duke Albert and Duke Ersi knew to themselves that it was not the case. They were certain that the one who was assassinated by the vampires was Duke Kleon, one of the three great Dukes of the Tarala Kingdom that was trusted by the 'dead' King to handle the General Governance—or the political affairs, concerning the Tarala Kingdom.
What was the proof that it was the real Duke Kleon himself? The letter delivered to Duke Kleon was good enough to serve as proof of identity.