Could this be considered a case of entrapment and emotional distress?

I suppose it depends on what you e mailed in conversation but I would call their bluff , every country has a police force that deals with fraud theft etc ,get the main Astrailian one which will be either in Darwin or Sydney or should I say the address of them and let the group members know that you have that address and are more than willing to contact them as you will already have their ISP and computer address.