Kyran went back inside because he sensed Tritus and his magic weapon's advancement had been completed. He did not warp to their location to avoid affecting the space, where the two were isolated, with the nature of his magic. If not, he might disrupt how they consolidated their newfound strength.
He still remembered Mannick's exhortation when he thought of going to where his father was.
Besides, Kyran also noticed Mannick with them; judging by the latter's aura, his mage level actually dropped by a few.
He recalled what Jared said about the Sovereigns' descent because the Human plane's cradle had already stopped working and how Nolan was forced to advance and become the plane's new Sovereign.
Honestly, Kyran had considered a scenario where Nolan ascends. But it was part of his worst-case scenario. After all, he had wanted Nolan's help to keep Haylee and her army at bay when the time to activate the Regis's Grand Array came.
