With the help of DeadMan we are currently testing an altered table partition, the WiiU can't see it, and the loader can still detect it (by using the correct check).
It's working, but I'm still thinking if it's a good idea to release it to public (it could be dangerous if they don't understand how it's working and what the option does)
The Loader can have a setting to Hide/unhide the drive to WiiU.
When setting the drive to Hidden (or Locked to USBloaders), the HDD would be hidden to ALL devices and programs, except USBLoaders.
- Not detected by other homebrew,
- not detected by computer (at least, no partition detected, you can edit it back with hexeditors)
With USBLoaders, there are also restrictions:
- Not Working with WBFS partition
- Not working with EmuNAND (use EmuNAND path on SD card, problem solved!)
(Or course, no DIOS MIOS either, if you use it on Wii)
I don't know if getting rid if the table partition has any other indesirable effect. maybe it could corrupt the data?
Edit:
What should be the best, is that all loaders use the same trick, so the HDD are compatibles with all loaders withut unhiding them first.