Kai had secured the Blue Gem and also took out Lion along with Team Coeus.
He had done basically everything for a team to pass this Blood Rite, while the rest of the students only needed to open their second Divine Lock. Of course, Kai having the Blue Gem came as a surprise.
So, he decided to explain the when, how, and why to them.
It was insurance against Lion and Team Coeus.
At least if he somehow failed to end them once and for all and managed to survive, he could count that they can't win the rite and leaving him to dry. Of course, he didn't tell them about how he used the Awakened Monster to kill Wolf and make a statement.
And with no Team Coeus among them, that would be his secret.
Not that any of them would mind.
