This Wii U was lent to me by a friend who attempted to repair it before Paid the Beak was discovered. The pico was left behind, and I used it as an entry to install ISFShax per tzirf's instructions.
My SLC dumps (along with MLC) were created using GaryOder's recovery menu + mlc tools. This was back when the Wii U could boot off the EMMC perfectly fine. However, they were dumped as slc1.bin and slc2.bin instead of the typical SLC,RAW and SLCCMPT,RAW. These files are not accepted by minute due to file size differences.
Last night, with a SD card flashed with my old mlc, the Wii U managed to boot but hanged at the Wii U splash screen.