hum, odd, did you also kill ModemManager? All these steps also are in the inventor so I suspect there is something else going on, like maybe some wrong library being used, etc. We used static linking against Qt 5.11.0 but there are still a bunch of dependencies (see ldd /usr/bin/jevois-inventor) and some different lib version may not work. Did you run sudo apt update and sudo apt upgrade lately?
First we detect the camera device (/dev/video0 or similar), and then the status bar at the bottom should change to
JeVois Inventor 0.1.0, camera device ok, wating for serial-over-USB
then we detect the serial-over-USB (/dev/ttyACM0 or similar) and the status should say "connected".
do you see that, or do you see "JeVois Inventor 0.1.0 waiting for JeVois Smart Camera"? (which is shown as we are waiting for the video device to show up).