Here's the log.
Checking for MD5 file...
Skipping MD5 check: no MD5 file found
assert failed: run_program("/tmp/test_radio_version.sh", "T989:UVMC6", "T989D:TLMC4") == 0
E:Error executing updater binary in zip '/sdcard/cm-11-20140923-Sultan-hercules.zip'
http://forum.xda-developers.com/galaxy-s2-tmobile/development/rom-kernel-unofficial-cyanogenmod-11-t2885259 (LINK to the ROM and kernel I used)
What's the deal with this error? Do I have the wrong radio version or something? I did a factory reset before flashing. I can give more info if needed.