Let's get something cleared up here a bit. There is no reason to consider the George Geef shorts to be in the same continuity as Goof Troop and its related media.
For one, the George Geef shorts very much take place in an era that was contemporary to the 1950s, whereas Goof Troop (as stated by Max in the episode "Shake, Rattle, and Goof") took place in the '90s.
Plus, the Goofy of Goof Troop's world attended college in the '70s, as he stated in An Extremely Goofy Movie, and couldn't get a good job until after he completed his final year of college in that movie, whereas the Goofy of the George Geef shorts was already a working employee in a white collar office job in his 1950s-set world.
Not to mention that the 1940s short "Motor Mania", in which Goofy was named both "Mr. Walker" and "Mr. Wheeler", featured Mr. Geef as a separate person from Mr. Walker/Mr. Wheeler, despite Geef being the role played by Goofy in the 1950s shorts. This was a common aspect of the 1940s Goofy shorts in which there were could be more than one of Goofy at any given time, such as in "Hockey Homicide" in which Goofy was every player on both hockey teams and every member of the crowd in the stands.
The point is, while all of these different individuals are Goofy in essence and concept, they aren't exact the same single Goofy in the same single world. I mean, you wouldn't try to claim that the Goofy from Goof Troop, the Goofy from Mickey Mouse Clubhouse, and the Goofy from the current Mickey Mouse reboot series are all the same Goofy who lived through the events of all three TV shows in the same single lifetime, would you? It's a case of there being one character concept existing in multiple separate continuities as different incarnations/iterations/versions/takes on the same singular character idea.
It's like how the Scrooge McDuck of the original DuckTales cartoon and the Scrooge McDuck of the current DuckTales cartoon are both valid takes on the idea of the Scrooge McDuck character, but aren't physically the same Scrooge McDuck person as the one from the newer cartoon did not live the same life as the one from the older cartoon.