...I literally toss all my old components into a big white cardboard box; there must be thirty pounds of old ISA modems, ethernet adapters, and video cards in there. It isn't good for them, but every single piece of hardware that I dig out of there still works... jumpers might be a little bent out of shape, but that's an easy fix. Not that I recommend it, but it can be done. Hardware can be a lot tougher than people give it credit for.
Your situation? 99% chance of there being no problems, as long as the box wasn't abused or thrown around - an anti-static bag won't stop damage from a physical impact hard enough for the heatsink to break something free... that would take on hell of a hit, though.
The temperature wouldn't be good for it, but as long as the card itself warmed back up to room temperature by the time you fire it up, it shouldn't cause problems. A lot of these BGA-soldered chips (like the GPU on a video card) have problems when the chip expands at a different rate than the PCB itself; the solder can become brittle, crack, and cause problems at very cold temperatures. Be wary of condensation from bringing a cold object into a warm and possibly humid environment.
These are just my opinions based on experience. Take them for what they're worth.