As high school continues and Kukui and Guzma still live together, Guzma perceives how Hala treats him differently, and suspects this is because he has chosen Kukui as his successor over him. Kukui is shocked to hear that Guzma thinks this, and shocked to hear that Guzma even wanted the position in the first place when he's mostly disavowed the spiritual movement in general. However, he perhaps subliminally likes the attention and confidence that Hala places in him. Right before their senior year, Guzma confronts Hala about this, and in addition to Hala not denying any of it, he tells Guzma about how the Tapu have rejected him as a candidate. Guzma, hurt and resentful, says he's going back to his "real family" and insults Kukui the whole way out.

He and Hala both try to reach him—Hala is especially afraid for his well-being, considering the circumstances in which he left his father's house, but Hala was never his legal guardian and therefore cannot force him to do anything. And Kukui starts losing trust in Hala at the same time, completely rejecting the Kahunaship. Under Professor Oak's suggestion, he applies for college in Unova to pursue pokemon academia.