This may very well be just semantics but I thought people usually refer to biological smells as "horrid sickly", not electric. So, I guess, the big question is: does the fridge still work? I had a feeling reading your question that it still does. Electrical smells tend to become really bad just before the thing breaks. You might actually describe electrical smells as "sour" or "acidic" most of the time, due to common presence of chlorine in the wire insulation which gets released when it's overheated (again, usually shortly before burning up).
Anyway, sorry for the detour but I just thought it might be important to eliminate electrical issues simply because they may be very hazardous. On the other hand, fridges and freezers have a natural source of great potential for foul odors - the condensed water that's nearly always available in the drains under the evaporation coil. They may become clogged and water does not get to evaporate and stays for long and bacteria flourish. When you say you scrubbed everything, do you mean insides? The coils and their drains are on the outside (back and under the fridge). Do you see any water standing or perhaps discoloration? It is important to make sure nothing blocks the condensed water dripping from the coil, into the tubing and out on the flat pan underneath where it can safely evaporate before bacteria take hold.