I readed the latest ideas you guys added, and wondering myself too who redjohn is. If I am looking at all the suspect, then the list of seven can be quit right, cause by excident Patrick gets to know that he once shake the hand of Red John. (I even think but was not able to di that, this means Red John is already once seen in the first season, because the writers probaly will show back to the first season were Patrick all met and been followed by red John.) Still it is quit impresive that he was able to make a list of seven out of his memorie, probaly something red John did not expect him to do. (He made a mistake)
About the Tiger Tiger club in the police force that is working with each other to cover things up, and have there own agenda. It could be that when they catch Red John, that they use a sort of twist were the new story line will not be red John but the cbI will have to go after the organisation of Tiger Tiger, were Red john maybe was a member from, and that why they want to catch them too. (Then you would have a extra season atleast)