It looks like the communication link between the Pixhawk and QGC is not doing well. The connection lost and missing parameters are both symptoms of this problem.
Please verify that the tether conductors are seated securely in the screw terminals on the Fathom X boards. You shouldn’t need to reload the parameters, this message means that QGC did not catch all of the parameters emitted from the Pixhawk.
How does the video look?