If we accept that Nick really is Third Party primary, it really does seem killing castiel would be a better option wouldnt it? They are mafia and even if they can't contact the other members, they are still counted among the mafia count for parity, meaning if we get rid of them, we push the mafia one step away from equaling our numbers. That of course is if they are third party really. Still i will wait to hear what Kiet says, if they confirm Nick is a TP i'll switch my eviction vote.
 
	 
 
	Pretty much if Nick is telling the truth then our best option is to delay the Mafia's wincon rather than leaving him alive, risking lynching a house guest or wasting it on a TP when we could achieve the same and better from killing a mafia.