Minor? Saved their leader and one of their essential artifacts for the story. Also fought off the faithless for them. Just cause the alliance is not canonically in the dungeon quest it does not mean their contributions weren't sizeable It doesn't have to be the faithful either.
But, it matters not. It can be the remnant of the faithless joining in search of redemption. Vulpera had no reason to join the horde until their scenario. Lore is made up. It serves the content.
The point is i want a more animalistic but still proud race for the alliance to make variety better. I think they fit the bill. It subverts expectations while keeping the alliance feel. Horde can get Ogres. Horde players clearly want that more. Even if they are neutral i don't mind.