Flashed a TouchWiz FW in CM ROM, device won't boot

I installed the Nvertigo ROM on the T800 and stupidly installed the TouchWiz SkyHigh kernel from TWRP. Unfortunately the device won't power on after boot? So I went to the "Download mode". Trying to flash original fw with Odin so that I don't have a bricked device. Unfortunately Odin is stuck at "Setup Connection..." while trying to install the OFW. After waiting for a bit it in Odin, it says "All threads completed. (Succeed 0 / Failed 1)". I did not know what TW was, stupid me! Any ideas?

UPDATE: Somehow managed to access TWRP, however, can't do a factory reset, says "E: Unable to mount storage"