KitchenAid Refrigerator Circuit Board

I own a KitchenAid built-in fridge (KSSC42FMS01) which was purchased about 10 years ago. It stopped cooling last week and I have had 3 technicians diagnose it with a faulty circuit board. The issue is none of the technicians know where to buy a new replacement board. I called Whirlpool and they said the part was on back order. I believe the model number is W10219463. I just don’t understand how this is not fixable. I mean this is an $8,000 fridge and the last thing I want to do is have to replace it. Does anyone know how to fix this or at least where I can find a new circuit board. I live in Toronto. thanks