I have tried with the device numbers as they appear in lsusb with the 0 in front USB084 and without.
I also tried -S /dev/ttyUSB084 as per jstefanop's post, 'for linux it will be /dev/ttyUSBx' however the example is '-S MLD:/dev/ttyUSBx'
Is there something I am missing?
The ttyUSBx number does not match the bus device ID. Navigate to the dev folder and search for ttyUSB*. You could just try ttyUSB0 and so on ttyUSB3... usually moolanders show up as the first usb devices and newpacs do not show up there at all. If you have been trying to hotplug them the number could change.