Alternative method for pokemon extracting:

If you use PR-extractor, you can check data of the trainer that deposited the pokemon (TID and SID). You can check the name at My pokemon Ranch screen or using pokegen and opening the .pkm file (only if the pokemon belonged to this same trainer).
If you edit your NDS savegame so it matches the TID, SID and name of the trainer that deposited the pokemon, you can withdraw them.