When you are GM forced into a setting, you tend to lose some of those rights. If you had a problem with the potential of Rei being played by other people, then you should have told Reynolds to not have her officiating the match.
Furthermore, it's a little immature that you are complaining over three lines of Dialogue. Reynolds stated you were the only one allowed in the ring due to your "experince" and thus you are the officiator. Rei "Officiated" the match. She got the ready, started the match, and called the winner. Literally three lines of dialogue. If that is going to bother you in the future, make sure your character isn't forced into other peoples scenes.