Hah, silly me thought I was home free for a while. This doesn't seem like the original door rattle (1st one dealer said was glove box), happens on different road surfaces than the 1st rattle and it's quite a bit louder.

Was doing a thorough cleaning/waxing and while lubricating the door seals noticed that one of them was starting to peel off already. Hopefully this is just in one spot and not a problem with the glue they used.

Update: Bought a rubber mallet and poked around, there are two vertical plastic panels between the doors, they don't sound tight on the drivers side. I then drove it slowly over cobblestones while putting pressure, it's the top one where the seat belt comes out of.
Have to see how this thing is attached...