I think I got a solution without using the exlink cable.
After successful hotel mode hack I made the same mistake with the factory defaults after some unwanted installations.
Had the same problem and got stuck at the "USB to TV" write back
Added (beside the usb_mount directory) the following directory structure to the channel list on the USB Stick:
network_opt/usr/sbin/usb_mount (no files, just the empty directories)
After I wrote the modified channel list back to my sammy, I was able to do to "USB to TV" write back
Worked for me.
TV: Samsung C6710 with 3008.3