Or, have one hold the gracidea flower(It doesn't matter if the flower it's self is hacked or not, it will still work on the flower paradice shaymin), and possibly make another a manaphy egg.
Here is that script editor(IT should work for platinum):
http://forum.pokesav.org/viewtopic.php?f=29&t=2446
Edit: It could be the one that you are using...
I have an idea. Edit the script for the arceus teleport(The HoH is a whole diferent location then spear pillar to thegame), canalave inn door(this may require the most editing), prof. oak's apearance script, and the dorr open script thing.
You do have to have beaten the E4 for them to work(I'm only for sure about the member card. You don't need to beat the E4 for the secret key). You also have to have the wondercard for them to work. You don't have to have the national dex, I think. You could make it so that the event would allways be activated.(By editing a file, that I do not know the name of )