Find an untouched, non-decrypted, and non-trimmed ROM dump. Users on r/3dspiracy often suggest looking for ROMs from verified archival sites to ensure they match official checksums.
Use an unmodified ROM
: Some ROM sources use "trimmed" versions to save space, which often strips out the DSi binaries. ROM Hacks & Randomizers : Tools like the Universal Pokemon Randomizer often break DSi binaries during the modification process. Old Dumping Tools The Dsi Binaries Are Missing Please Obtain A Clean Rom