Newer games use 2 methods to stop you from using any of the older methods to play games.
The first is larger hardware requirements, things like larger save file sizes etc.
The second is anti-rom code.
Newer pokemon games employ both. The first method will eventually kill the passme ability for newer games eventually. This is what you face, your only current solution to this is use a slot1 flashcart that supports this game.
Passme was made in the pre-SDHC era to expand beyond the 2GB limit of most flashcarts in the day. Using passme in the SDHC era makes it's use redundant and cubersome when someone wants to use cheats. 8GB and 16GB are already affordable.