hi! I'm having trouble with this problem as well- I'm literal newbie to hacking. Did you ever find out? If so do you mind telling me? Thanks.
EDIT: NVM I got help.
I get the same error, but for Fire Emblem Fates. Did you find a soultion, and if so how did you solve it? Thank you.
EDIT: Nvm haha I fixed mine. I don't think my file was correctly decrypted, because I redecrypted my game and it worked just fine.
although i ended up accidentally changing my nand with no way of going back bc i didn't know you needed a gamecube controller to restore it (i have a wii minus/1.1, which doesn't have gamecube controller support)
and if i find the sd card i have my NAND backed up on, i can not only restore the NAND if i solder the right part in, but i can also put my NAND on dolphin, then i can play dolphin online, like PMEX Remix or MKWii Riibalanced