You need a dump of the original Japanese game. Search for the following CRC32 hash to verify you have a clean dump:
Cause: Wrong ROM version. You used the "Rev 1" or a pre-hacked ROM. Fix: Find the original 2004 release (no "Rev 1" in the filename). medarot ds rom english patch
There are two versions of the original game (Kabuto and Kuwagata), similar to the Pokémon series tradition (e.g., Red/Blue). You need a dump of the original Japanese game