Ive done lots of winter camping and survival camping and would jump at a chance like that.  You could have improved your shelters, even if you didnt have time to build a quincee, by building snow walls, i saw a shovel in the picture.  A tiny little fire will warm you, you dont need a roaring mofo, just twigs in a good shelter will warm you.  The coldest i have been out was
-40 plus windchill and i survived fine, i just think you should have looked into winter survival before you went as you knew you had to do it.