Lipo, Giulio, Remco ... are now too big stars, to ride for Rogla, although Remco never rode with Rogla so far. On top of that a mentor, such as Rogla, can't exactly gobble the protegee, racing for second place. Beyond that Rogla was all over the race, doing Rogla things. At Swiss on the other hand it's full on racing.
Note that any other rider joining this club must beat Pogi not only with grit, determination and masterclass positioning, beating must come while Pogi is still is winning the Tour, just like Rogla did, otherwise it won't count.