37th Dolan's odd omission of the simple detail of Witch Queen's heart being stolen sounds like a moment of idiocy until you learn that 37th Dolan is actually Witch Queen's mole in Axe and Cross, meaning he might have purposefully avoided telling Kaulder this to slow him down.
First Dolan's calm reception of Kaulder's zombie-like state shortly after Witch Queen's death may be him being cold-blooded, or it may be the result of him being a priest and thus going around giving final rites to people who were dying of Black Death.
The scene in Chloe's house seems out of place and pointless, especially from Belial's point of view, until you realize this isn't authors trying to give us some Nightmare Fuel. Belial's trying to kidnap Chloe - a young witch who's a Dream Walker - to act as a host for the Witch Queen. Even him blowing out all the lights was necessary, as his Black Magic only works in the shadows. It's only after this attempt fails that he goes for Max, who's not only a man, but also blind - in Belial's opinion, certainly a sub-par host.
Hexenbane is the perfect tool of witch-killing: the motto of Axe and Cross is "by iron and fire", and indeed, it's an iron sword that can be set on fire.
Kaulder takes the precaution of pretending to go under the effects of the spell Chloe made. It even seems like a justified action as Chloe checks that he's under and kind of hovers beside him. Turns into a Funny Moment when she just wanted to take a selfie, and he startles her by revealing he wasn't actually under.
