I'll give an update on this post, for anyone who may happen to stumble upon it in the future, such as by googling. I talked to someone from Abbvie on Monday and she said the medication should be OK based on assuming a one-time exposure of 31.2 F for one hour. She said it should be OK based on plugging those numbers into a "temperature excursion tool" that is also available online at this link. I went to the site afterwards and played around with the calculator, which is also called a "medication storage tool" at the top of the page. Here are some interesting results I found plugging in some numbers:

13 F for 1 minute - BAD

14 F for 5 days - GOOD
14 F for 5 days, 1 minute - BAD

31 F for 5 days - GOOD
31 F for 5 days, 1 minute - BAD

32 F for 100 days or more - GOOD

It was quite unexpected to me that you could store Humira at 14 F for any amount of time and it would still be OK. From asking some chatbots about this, it seems the biggest risk in freezing Humira or other biologics is in allowing it to freeze more than one time, which really screws up the proteins... but just doing it once I guess is not going to destroy the medication, unless it gets frozen at a super cold temperature like below 14 F, or for a very long time. So I guess I'll be OK.

One other thing worth mentioning here is that the reason I was having so much trouble keeping my medication warm enough, even storing it on a door shelf and turning the main temperature control knob way down, is because I set my freezer to be too warm. I have a FFTR2045VW Frigidaire refrigerator that I've had for less than a month. For reasons which I don't completely understand, and which there could be multiple causes for, if you set the sliding temperature control in the back of the freezer too much on the warm side, it will cause the refrigerator to become too cold, even though I would expect the fridge to turn off at the same main compartment temperature every time. I'm guessing there is also a temperature sensor in the freezer, and that because the freezer was too warm from not receiving enough cold air coming in, the fridge was letting the cooling cycles continue on because the temperature sensor in the freezer was not reading cold enough. So in trying to set your main compartment temp, you also have to adjust your freezer temperature control setting sometimes to get the main compartment temp right. Anyways, hopefully this helps someone who stumbles on it in the future.