They were wolves. Variks was the only one who didn't betray the queen. Even says he is the only one. And he is the only house of judgement. He says it himself. In one of the grimmoir cards he talks about how in a the past the house of judgement was the closest thing to peace the fallen ever had. Once the traveler left the fallen they broke into war with themselves and judgement was wiped out. He is the only house of judgement fallen. And I dont think that any fallen guardian would be house of judgement by default. That would be their choice on what house they swear to. And being a a guardian means being selected by a ghost(dead or alive) so they would likely be involved with the tower.