Okay, so "Completely Cold" is in neither Land of the Dead #1 nor Jon Sable #4. Someone else's story is, but I'm pretty sure I know why.
Apparently "Completely Cold" is running in all the IDW books that were solicited for September, not that actually come out this month. Jon Sable, for example, was supposed to be a July book, so it has a the first half of a story that ran in all the other July books. Land of the Dead was solicited for August, so it's got the second half of that story.
So, looking at IDW's solicitations for September, I think I can compile a fairly accurate list of the books that'll have "Completely Cold" in the back:
Metal Gear: Sons of Liberty #0
The Keep #1
Land of the Dead #2
Night Mary #3
CSI: NY -- Bloody Murder #3
Jon Sable, Freelance: Bloodtrail #3
Shaun of the Dead #3
Angel: The Curse #4
Hopefully at least one of those will ship on time or at least before FallCon. Since Three Days the Devil Danced isn't going to be ready by then, I'd like to have something new on my table to show.
Update: I'm going to grey these out as they're released.