There must be some mistake. The FBCOD is encouraging players who do not have the original game to get the key as in partnership with a company that sells the key to the game. Will not be allowed to participate in our events, players with games that are not original. Please review this, some error is actually happening. Below I copied a few lines of the file server.cfg so you can see:
/ / Master servers
September sv_master1 "cod4master.activision.com"
September sv_master2 "cod4authorize.activision.com"
September sv_master3 "cod4update.activision.com"
September sv_master4 "master.gamespy.com: 28,960"
September sv_master5 "master0.gamespy.com"
September sv_master6 "master1.gamespy.com"
September sv_master7 "clanservers.net"
September sv_gamespy "1"
Review what they did to me, neither of these two servers in question allows the entry of players with key invalid. Unless, a server that has added to my account (SOD), at the request of a clan leader, was in this situation. If it was, I did not know. But I guarantee that the servers FBCOD are clean and require original key.