Welcome to the forum, sure somebody will be able to give you a more specific answer but I believe if the towbar is electric then the foot opening of tailgate is disabled.
Enjoy your car when it arrives.
2017 GLC AMG43 premium plus, night pack, leather, intel lights, 360 camera, side steps. = sadly gone
Now GLE450 Premium plus, Selenite, Black/White Nappa leather, Tech plus pack, Driving assistance pack, Tow pack, Off road pack, 22 inch wheels.