With the errata of Long voyage, now said only neutral faction and i understand its considered a house, if you play spending the.... can you look for a neutral attachment?

No. There are no "in-House" cards when you play Neutral Faction - including other neutral cards. "In-House" means cards with affiliations that match the affiliation of your House card. Neutral cards, including the Neutral Faction House card, have no affiliation (it even says that right on the House card) to match, so can never have an affiliation that matches anything.

"Nil" does not match "nil" in this game.