USB Drive Compatibility List
check the fat32 loading guide (link below)
and download the app_pack from the softmod any wii guide (link below)
"your" ios is not 58, maybe you installed it or something.
if you are interested you can check your, the wii's iIOSs using syscheck (Instructions here)
BIG EDIT: If you stopped any modding after installing only the hbc and bootmii. you are NOT done yet.
you have to get a working cIOS. from your statement you likely don't have one and did some strange guide, from different source (youtube?). did you softmod at all till the end? yes, use the sofmod guide, only a few steps remaining. can all be done from the homebrew channel. also get your nand backup using bootmii. check the guide all there, read -> and then slow steps