The radio has DB19 connector in the back.
The interface cable to Digirig will look like this:
DB15 pin #8 (PTT) → 3.5mm TRRS ring 2 (RIG_PTT)
DB15 pin #10 (LINE IN+) → 3.5mm TRRS ring 1 (RIG_AFIN)
DB15 pin #11 (LINE OUT) → 3.5mm TRRS tip (RIG_AFOUT)
DB15 pin #15 (GROUND) → 3.5mm TRRS sleeve (GND)