I have used it multiple times to repairs some bricks, but I also had a modchip and a wode so I was able to mount special recovery discs.
@OP, if you uninstalled the system menu wad, then you are currently stuck. Even if you reinstalled it, uninstalling it removes some specific files that will not be put back in place by reinstalling it. There is a process to repair it, but it has been so long that I forget what needs to be done. If you have absolutely no access to the homebrew channel or any other means of running homebrew then you are essentially screwed.
Your only hope is by restoring that nand backup, which requires a hardware flasher. But without a hardware flasher then I see no way of repairing the wii.