But remember: The Annual meeting article does not claim there WAS a GB back in '25, the quote goes:
"From 1919 on, there has always been a small group of anointed Christians at the world headquarters of Jehovah’s Witnesses. They have supervised our worldwide preaching work and have been directly involved in preparing and dispensing spiritual food. In recent years, that group has been closely identified with the Governing Body of Jehovah’s Witnesses.
The evidence points to the following conclusion: “The faithful and discreet slave” was appointed over Jesus’ domestics in 1919. That slave is the small, composite group of anointed brothers serving at world headquarters during Christ’s presence who are directly involved in preparing and dispensing spiritual food. When this group work together as the Governing Body, they act as “the faithful and discreet slave.”"
So there has been a group, and in later years, that group has been identified with the GB. It does not say there was a GB right from the beginning, or that there was a GB constituting the slave.