Okay, go into the ini and get the offsets for the frontspritetable and the frontpalettetable.
Now, we need to jump ahead, so we need to add on how many pokemon we have. Each entry in the table is 8 bytes, and we need to jump ahead 0x244 pokemon. So...
Open up Windows Calculator and switch to hex mode. Now do:
frontspriteoffset + 244*8
and
frontpaletteoffset + 244*8
Now you have the new offsets. Go to each one in a hex editor and write down the next 4 bytes you see. This is a pointer. It will be in the form of AB CD EF 08. You can cut off the 08 (that tells us it is in the rom) and then reverse the bytes like this:
AB CD EF -> EF CD AB
This is the offset of the sprite/palette depending on the table you went to. Write down both numbers.
Now, go to those locations and you should find just FFs for the length of the sprite/palette. At the sprite location, paste the blank sprite I sent you. At the palette location, paste the blank palette I sent you. This should restore them to what they were before they were overwritten.