Just like OP I didn't know that 4.3's bootloader was not un-lockable yet.
Here's how I bricked my phone and what I've tried so far.
ROM: 4.3 Verizon (Stock)
Rooted with SafeRoot
CWM Recovery was installed.
I used EZ Unlock and it reported Success to unlocking the bootloader.
To fix it I've tried this http://forum.xda-developers.com/show....php?t=2581166
I don't have a class 10 card yet to try.
Does anyone have any ideas on this? Is there no built in way to recover it without a hardware JTAG?
I'm trying to figure out if I can fix this with software without going to my carrier or sending it to someone for $100+.