Sylvester had thought a lot about the Demon in the Divider Swamp. As a Grand Wizard, he knew he couldn't challenge it alone, nor did he have any Supreme Wizard experts at his disposal. If he wanted to deal with it, he was going to need the help of the supreme overlords of the Beastaria, from the dragons, dwarves, Beastkins, giants, vampires, and elves. However, with his current status, the best he could hope for was to rally his father's support or, in the best-case scenario, a possible Supreme Wizard from the Beastkins, if there was any.
Hence, the thought of the Demon being a blessing rather than a bane rose in his mind. Currently, he didn't really need to do anything but pass the information on how powerful the foe was to everyone. Indeed, it was a risk, but it was better than throwing himself into a new mess while the existing ones remained unresolved.