It's far too obvious in the new footage that it's just an outtake of Vader arriving on the Death Star II. The hangar is the DS2 hangar, and what is Moff Jejerrod doing there (mouthing his ROTJ lines but with no sound coming out). That either needs to be removed, or some clever digital manipulation (insert Piett in there? Change the background?).
^^ I think the amount of work it would take to insert Piett and actually make the hangar look different isn't worth it. This is probably an area where Ady could just change it back to how it was originally.