First off, sorry for your bad experience. I had something similar happen to me in Utah when high temps at the bottom of the mountain were 5 degrees and then 11 degrees.
All goggles will fog if exposed to enough moisture and not enough moving air. If you were hiking in the goggles, then you were sweating which produced more moisture than normal and moving very slowly which would not have produced enough of a breeze to evaporate the fog that collected on the lens.
The only solutions available in that situation:
1. Remove your goggles and finish your hike without them (or remove them when they get fogged and put them back on after they clear up)
2. Carry a spare set of lenses or goggles for when they freeze up
3. Open up the vents on the goggles (if they have adjustable vents) to allow as much air as possible through them.
4. Use goggles with a built in fan so that air moves through them no matter how slow you are going
IMO, #2 is the best solution. I carry spare lenses and spare goggles when I ride. (The one time I didn't, I needed them and rode all the way down Peruvian at Snowbird with no goggles when the high was 11 degrees and it was windy/snowing...not fun). Spare lenses and goggles will save your bacon when lighting conditions change (on those partly cloudy days) and from frozen lenses.
First year to try Oakleys. Previously, I've only ridden with a pair of Spy goggles. The Crowbars are a good fit to my helmet and the pink lenses were perfect for my light conditions here.. On the second or third time, I was hiking up Whitewater and worked up a good sweat. They fogged up abit on the inside but I knew better than to wipe them. They turn to ice, obscuring my vision. I'm standing at the top of a pretty narrow chute, and it is new territory for me. I figure, do I really want to risk coming down this powder haven with no goggles or worse yet, poor vision? One second, one decision, one regret. I dabbed the inside with my microfiber cloth. It became a slight rub. Abit more. Seems ok, so i do it more. blow on it with my breath and rub on it. By the time i get to the bottom, I have a scratched Crowbar. I'm not sure if it's because my spy goggles just didn't have an anti-fog coating, but frick is that anti-fog coating fragile.
This thread is for anyone who has lost what seemed to be a good pair of goggles before it's time had truly come and has become an old man filled with regret, waiting to die alone.