Can I Wire the Current Input to Both the Direct Input and External Sensor Input Terminals?

NO, you should not use the instrument with both the direct input and external sensor terminals wired. Doing so will put the user at risk of electric shock and could damage the instrument. This is because the external sensor input terminal's Lo side, and the Lo side (+/- terminal side) of the direct current input would both be at the same electric potential. When inputting a measurement signal to the direct input terminal, you must remove the shunt connected to the external sensor input terminal, and the current sensor.