I've spent roughly 24 hours trying to troubleshoot this independently; I purchased a 2TB external hard drive to store an entire backlog of Wii and GameCube rips that I know work flawlessly (no funny skips or anything like that) and were working just fine on a 128GB flash drive. After moving everything over and doing some tests, the Wii games work flawlessly but the GameCube games specifically will prompt "An error has occured" with timing as short as after Press Start or as long as 5 minutes of good gameplay. I've rewritten the IOS files to ensure there's no duds, I've patched and updated virtually every app with Open Shop, each game is named correctly with the correct IDs, named as game.iso, all of it. At this state I'm run tired and I've exhausted my options.
I have a slightly newer model white Wii (can't accept DVD playback), both my SD card and 2TB drive are properly formatted into FAT32. As stated before, the cIOS installation in all 4 slots is properly done (redone in this case due to a dud error I got). While the 2TB external is only powered by a single cable with no external power, my friend has a similarly set up 2TB external setup with only a single cable with no external power and theirs is working just fine.
Any help on this would be vastly appreciated, as I have roughly 200+ games backed up here.