And his role is so short you'd swear they bumped into him in a hotel hallway and begged him to improvise a scene! Hardly surprising he didn't take a credit!
Tagged, in order: Ma Hon-ngai, Cheung Wai-kau, Wong Yin-tou and Wong Chak-bo. All new IDs according to the cast listing. The one I wasn't able to ID is Jiang Wei, but I suspect it might be him:
Also, I didn't notice Cliff Lok or Angela Pang in the movie. The portrait gallery seems pretty complete to me and they're not in there either. They were in one of the other entries in this series, Rake Gambler. If nobody objects I will remove their credits soon.