So I confirm Curt 56434 is the correct part number for PHEV
See picture of the tail light connector compared to the curt
I did modify the harness as it is made to be installed on the left side, but since the PHEV battery is located on the rear right side, it is easier to install the module there
I swapped the green and yellow wires on the Curt harness, to invert the position of the right and left blinker
Also note, if you unplug the battery with the electric tailgate open, you will have to close it manually, as it seems to have loste It's position when reconnecting the battery and will not operate.