Nice sumarize of xp bonus. Yep I had to forget the Keeper of the Light skill, its green rune cost is a lot too heavy for Warrior and Mage but for Paladin it's fine. The 65% is rather optimistic it's not only against Demon & Undead but against army with only Undead & Demon, very few fights match this definition. It's still a skill to get for a Paladin needing XP.
Also I tried compute the chance to get both Dmitry & Neron with Mirabella, if I'm not wrong the chance to get both with 4 babies is 7,33%. Not impossible but still quite low for a complex scouting when selecting a game.
A more reasonable approach would be to try select by scouting a game where first baby of Rina is Dmitry for 10% XP bonus and still 3 free slots with Rina.
That should not be too long to scout and the chance of this is 11.5%.