OK, I'll take a shot here.
Since there's no before and after picture possible here, there's no way to tell if it was assembled in that fashion, or if in fact the inner bead is compromised and has started to shift. A side view of that seam looking through the side panel (from the right side of the top-down view) would be helpful. If it is in fact compromised and shifting it would look very different from the other four seams, and you should be worried. If that is the case, the panels are being held together by the outer silicone bead with the inner bead being totally compromised. That would not be good.
Angelo
"Why can't my wife see all of this stuff as an investment?"