There's one question I have about the whole scene. Shouldn't Halsin lose his druidic powers for fooling around with a vampire spawn?

Just think about it, a character that has to be attuned to nature, allowing something unnatural to be around...

It's just a thought. I know Larian doesn't really care about the mechanical side of DnD influencing the narrative that much. Considering they have rewritten Gale into Karsus Jr, and Wyll also has much more field experience now with his rewrite, starting at level 1 for these guys is much weirder now.