OK, just to finish a thread no one but me really cars about......
I ordered a replacement defrost heater and it finally arrived at my favorite old time appliance store. An old family owned store that has been in business for many decades. The Formica countertop is worn down to the base backing material in places. They have old school parts manuals that go way back. A computer system from the 80s, green text on a 14 inch monitor. They did have a laptop to connect to the internet, so not all old tech.
Anyway, $104 later it is a 20 minute project to empty the freezer, remove the ice maker to get it out of the way, removed the light bulb and 4 screws to unbolt the back panel, unplug the connections for the defrost fan, and have access to the evaporator coils. Snap the heater in place, plug in the two wires, and reassemble. Ta Da!
It sure beats paying several grand for a new fridge that will not last but a few years, and way way better than a new 10 grand fridge that is quality.
The compressor was just a little low on refrigerant at first, and that is taken care of as well, but that was not the real problem.
Now I have to have Mrs, Carrera supervise the placement of the food we store in the freezer. I am not competent to do that evidently. She "lets" me fix things, and mow the yard and one per week I get to take the trash out.