Ok, I'm having trouble understanding exactly what is happening here. You can flash anything via Odin, but cannot boot into it afterwards unless the sd is in? And then it won't boot what you just flashed, only stock?
Or is custom recovery getting replaced with stock when you boot?
What does Odin say in the message box after flashing? What debrick.img are you using and what firmware are you trying to flash?
You said before you flash the JC firmware, but is it LJC or MJC?
What happens if you boot into TWRP and flash a rom from there?
Sorry if I'm just reading wrong, but I'm just confused as to what you are doing and the results after.
If you can boot to download mode with the debrick sdcard, you should then be able to take it out, flash stock firmware via Odin, then reboot normally. Or flash TWRP with Odin, then reboot recovery. You should no longer need the debrick sdcard at this point.
If that doesn't work for some reason, ill need to know how it bricked. What exactly did you flash? And when you do try to boot without the sd, does anything happen?
Sent from my SGH-T999 using Tapatalk