So, today @pedro702 did a couple more tests for me and we got the gamepad data read out using the same fw.img as I already used the other day (the crc32 e2f27e9b one).
First you need this simple patch:
offset 0x1478A from 0x6818 to 0x2000
Set drc_use to that value needed for the gamepad classic controller emu to work, you can still use homebrew as you normally would in vwii mode, using a real wiimote with that patch.
Then there is this patch that moves down the gamepad data area low enough so wii apps can actually read it out with memprot and ahbprot still enabled:
offset 0x119A0 from 0x138BA004 to 0x13210000
And lastly, just to give a quick thing using the gamepad in wii homebrew I threw this demo together.
https://mega.nz/#!hlZlxCyQ!igqT2_jUXQnIHVwE2MCA9UVhLRUxBRT4HIfgn5_77AY
It just prints out all the buttons/sticks on screen, source is included.
While it is not much at least it shows that yes, you CAN use the gamepad outside those official wii games