I would say that silver chains would be a good start. Blood bonding might be good too. Dominate might work, but it could be hard to tell how well the Dominate has taken effect. You don't want to release a werewolf that you think is Dominated but actually has resisted. Maybe you knocked a werewolf unconscious, you could keep it that way with drugs. Kind of like an induced coma if you have the medical equipment and knowledge available.