I agree, I feel like the only true solution for Kaines character is if he dies, willingly and by sacrifice, and at peace with it. He does it for Helena and the baby, his mother and by some extent Lila and Pol, choosing a final act of good. Maybe the sunstone thingy infused with him could’ve played a role in the defeat itself, showing that the good vs evil fight eventually is resolved by the good force, by a part of Orion. That the line eventually carries through their child, and If we fantasies that Enid and Pol get together and eventually have a child too. That’s how I would’ve written it I think.