So guys, I dropped my DS off this morning for the repair. I had one of the techs accompany me on a ride to hear the second squeaking noise from the trunk area. So during the ride, he showed me the noise coming from the pillar and how to physically replicate it without driving. He pressed the area slightly above the pillar and more on the headliner area...to the right...if you press on it, it will make a popping noise. That's what they're going to address initially. And during the ride, I pointed out to him it actually makes this ticking sound like a metal needle tapping on a metal surface sound when I drive on a typical city road (not smooth). The other noise, aka squeaking from the trunk, he was also able to hear. He rulled out the cargo cover making the noise and he said he'll look into maybe lubing some rubber seals since it only squeaks when the vehicle was rolling over bumps/potholes.
Off topic...slightly, does everyone with a 2016 DS with no 5+2 seating or a tow package have an opening in the rear lower bumper? I brought that up to the service rep and sales person. They noticed it on other deliveries as well. It seems to be cut for those said packages above but I never ordered it with mine. Just seeing if any dealers addressed that out there. I'll try to keep y'all DS nuts posted on this. Happy Holidays, y'all!