With the 7s, you have to have at least that part foamed. The rest can be naked; I've tried with no light leaks. But to say what will be fogged really depends on how much the camera spent in the bag, did you have a half case and how much time between shots did the camera spend in strong sunlight/light. I've had good success with only the hinge foamed but YMMV.
VC Bessa R3a & Leica M4-2
Yashica D TLR
Assorted unRF SLR's
Hoping for R4m or GXR-M
For Pete's sake, they're all good. Just get out there and shoot with what you've got!