So the phone's about a month old, maybe more. I don't think your situation is the same as everyone else's here. The reason the manual method didn't work for you is because those img files are not loki patched for 12b. You would have to push twrp.lok and loki flash with adb in order for the manual method to work for you. (Those files are here).
Shelnutt is the developer of freegee and he did say that he pulled 12b support from freegee so I don't know how you were using it.