So both Target Type and LV2 Kernel are CEX in the System info in rebug toolbox?
Only a few things i can think of to solve it but might not work.
1. Format The USB and re-make the files PS3>UPDATE>then the cfw
You must login or register to view this content. -Try this, this is the 999 rebug the file you have might be corrupted
2. Install the CFW through recovery.
I might have another solution but is QA Toggled? and when did you toggle it if you did?