I am running Kubuntu 19,04 and attempting to use MultiWriter to make a bootable usb stick for an iso. When I try to launch the program, it starts and then closes down without explanation. I am unable to locate the program in the home directory to launch it from the command line. I am a relative noob to both Linux and Kubuntu, so I may be overlooking something. any advice would be appreciated.

You should be able to right-click on the application launcher shortcut and select Edit Application. This will open up a dialog for configuring the application launcher. You'll find the actual command listed under Application -> Command which you can copy+paste (removing any % part which would be a placeholder for the file(s) being passed into the application).