During the Beggar's Union conference in DGSD, Kiu Fung expressed his doubts that Mo Yung F'uk was the killer of Deputy Union Chief Ma by saying that he had previously encountered several of Mo Yung F'uk's subordinates (i.e. Pau But Tung and Fung Bao Ngok, etc.) and found them each to be honorable, just, and compassionate men. Kiu Fung expressed a belief that such honorable, good men could not be followers of an evil man.
As it turns out, the Mo Yung family actually was quite evil, but what about those henchmen? Were they good men who happened to follow an evil boss, or were they just as bad as the men they served? If they truly were evil, however, how could Kiu Fung have missed it? Kiu Fung wasn't omniscient, but I think he was a good judge of character.