Maybe that one's shell was just a little thicker? Who knows... what I can tell you from my experiences is that the *only* time I see the swollen head, swollen neck, swollen belly, and the thick membrane is in my incubator eggs, I never see this in eggs under hens.
I don't think too low would cause that. In my RCOM, the 4 corners of it, temps run a little low and humidity runs a little higher there too. It's always in those four corners that I see this problem, it's never in the six center spots.