Hi leo,
You put 2 files SWI9X50C_01.14.03.00_TMO_002.005_000.nvu and SWI9X50C_01.14.03.00.cwe into the folder SWI9X50C_01.14.03.00. Restart the module (AT!RESET). Then try using absolute firmware path.
Example:
sudo ./fwdwl-litearm -m 4 -t 1 -d /dev/ttyUSB0 -c QMI -f /home/user/Documents/FW/FW.14.03/ -p /dev/cdc-wdm0 -l fwdwl.txt