Well, I am so very clever. I put my mittened hands around the keyhole and breathed into it for a while. There is a reason I didn’t tell you the first time. Clean mind! Eventually it thawed enough for me to be able to turn the key.
Truck is fixed again. Yay N! He has not driven since he got the license. Bless his soul, he understood and did not complain. We are probably buying a third vehicle this weekend. Brand new. Hopefully no issues!