So to try to fix it, I used odin 3.07 and the
stock rom file to try to put it back onto stock. Odin "stopped working" and crashed and I soft-bricked my phone (Firmware upgrade encountered an issue message at boot).
I tried again using I9300XXEMC3 stock rom, but odin 3.04 says
<ID:0/004> Odin v.3 engine (ID:4)..
<ID:0/004> File analysis..
<ID:0/004> Get PIT for mapping..
<ID:0/004> Firmware update start..
<ID:0/004> NAND Write Start!!
<ID:0/004> Complete(Write) operation failed.
<OSM> All threads completed. (succeed 0 / failed 1)
Can I please get some guidance? I don't know what I did wrong. What rom should I flash with odin? Should I try to flash the SGH-T999 stock rom with odin?