Can you set a GBA Game as Slot 2?

I'm playing Pokémon Platinum, and I've read that you need a Pokemon FireRed game in the second slot to catch a Magby.
This is problematic for me, as I do not have FR.
I play Platinum on my R4 Card - Would it be possible to use a FR Rom as my second slot?
I know it's possible to do it with a first slot DS Rom, which I've done for Pokémon on the Wii.Anyway, I hope you can help,
and I'm sorry if this is in the wrong section, but it seems flashcart related.

Sorry, I didn't phrase it well :/For Pokemon Platinum, to catch an Elekid, you need to have Pokemon Fire Red in the GBA Slot while on a specific route.
I don't have Fire Red, but would there be some way to use the Rom as a Slot Two, but to not play it? Just so the Slot Two thinks it's there?
I'm sorry if I'm unclear... :/

There is not a way. You need the legitimate carts.