AT&T Galaxy S4 Firmware Issues/No Kies/No Odin

Hi - I have a Galaxy S4 (AT&T SGH-1337) and it's stuck on the "firmware has encountered an issue screen." I'm able to get into download mode though.

Here's my problem. I went to Kies and tried to do an emergency firmware install and Kies tells me it can't verify my S/N from the phone. So I went and tried to flash a stock ROM through Odin - that failed.

Now what? Please help!

Thanks a bunch!