I think you're smarter than you give yourself credit for!
I was able to install Rock Band 2 DLC into Rock Band 3 using your method. Here's what I did:
1. Using RiiConnect, put all the RB2 and RB3 songs in the 'wad2bin' folder and run the bat file.
2. Follow the instructions to install wads to...
Greetings!
I've been having difficulty getting DLC to work with Rock Band and Guitar Hero. I've followed the instructions on WiiGuide to mod my Wii using LetterBomb. I've also installed the RiiConnect wads. I have a 2TB HDD and a 16GB micro SD, formatted to FAT32. I'm using USB Loader GX to...
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