After winning the Semi-Finals portion of the Champion Cup, you will return to Wyndon Inn. You are set to have dinner with both Leon and Hop, but after Leon doesn't show up, Hop will suggest going to find him. Oleana will appear and inform the two of you that Leon is in a meeting with Chairman Rose at Rose Tower just north of Wyndon (only accessible by the rail Station). Not satisfied by this, Hop will suggest heading to Rose Tower to retrieve Leon anyways.
This will upset Oleana, and will cause her to give the rail pass to Rose Tower to one of the Macro Cosmos Employees. After she does, it will be up to your trainer to find this Employee three different times in the Wyndon Entrance Area. Each time you do, you will go into battle with him. Defeat him three times and you will earn access to Rose Tower. You, Hop, Marnie and Piers will head there immediately; Marnie and Piers will keep a watch outside Rose Tower while you and Hop go in to find Leon.
In order to reach Leon and Rose at the top of Rose Tower, you will need to take the elevator going up. Along the way, the lift will stop and Macro Cosmos Employees will battle you and Hop in various Multi-Battles. Defeat all the Macro Cosmos Employee that stand before you in order to make it to the rooftop of Rose Tower.
Macro Cosmos' Eric: Level 47 Mawile, Level 47 Excadrill
Macro Cosmos' Eric: Level 47 Ferroseed, Level 47 Steelix
Macro Cosmos' Elijah: Level 48 Durant
Macro Cosmos' Jane: Level 48 Cufant
Macro Cosmos' Mateo: Level 48 Bronzong
Macro Cosmos' Kevin: Level 48 Klang
Macro Cosmos' Carla: Level 48 Mawile
Macro Cosmos' Adalyn: Level 49 Steelix
Macro Cosmos' Justin: Level 49 Galarian Stunfisk