This sound to me like you're trying to do piracy, but I'm not sure, so...
Delete the NAND dump, go to your friend's Wii, boot the game and move all DLCs to the SD Card, then, copy this SD card content to sd.raw file and see if the DLCs load.
The another way is going to your friend's Wii, booting the game, moving all DLCs to Wii Internal Memory. After that, go to Wii Menu => Settings => Save Data => Wii and copy the JD4 save (the one with a shopping car icon, with bigger size) to the SD card. Then, on Dolphin, go to Tools => Wii Save Import and then load the data.bin from sdcard/private/wii/*
Delete the NAND dump, go to your friend's Wii, boot the game and move all DLCs to the SD Card, then, copy this SD card content to sd.raw file and see if the DLCs load.
The another way is going to your friend's Wii, booting the game, moving all DLCs to Wii Internal Memory. After that, go to Wii Menu => Settings => Save Data => Wii and copy the JD4 save (the one with a shopping car icon, with bigger size) to the SD card. Then, on Dolphin, go to Tools => Wii Save Import and then load the data.bin from sdcard/private/wii/*
Avell A70 MOB: Core i7-11800H, GeForce RTX 3060, 16 GB DDR4-3200, Windows 11 (Insider Preview)
ASRock Z97M OC Formula: Pentium G3258, GeForce GT 440, 16 GB DDR3-1600, Windows 10 (22H2)
ASRock Z97M OC Formula: Pentium G3258, GeForce GT 440, 16 GB DDR3-1600, Windows 10 (22H2)