What I have done in the past is taken Von Schill and Angelica when facing Neverborn. Von Schill is great at taking apart minions and defends reasonably well against Pandora with his Stubborn knocking his willpower up to 8, and Angelica makes most of your crew immune to falling back from Mental Anguish, Pandora's most dangerous ability.
So, VS will dismantle that 4 dmg bubble, Angelica will keep Colette from falling back, and then you simply use your Soulstones to be able to cheat above Pandora (with your +ve flips from Collette's ability.
If you're dead set on using Kaeris, you're going to have a difficult time, because while WP 9 is nice (after Burning Heart), you can only do that so often, and your blast damage really isn't that impressive all things considered.