I didn’t so much post it for his benefit but other people’s benefit that may read it later on.
The most important factor which makes adapting a refrigerator to an air conditioner mostly pointless, is that the actual capacity of even a large (in comparison to Europe) American refrigerator is about 1/10 the smallest window air conditioner you can buy. We’re talking 500 BTU/hr for the refrigerator and 5,000 BTU/hr for the air conditioner, which is meant to cool at most just one small room with decent insulation and windows.
The fact that a refrigerator/freezer gets a lot colder doesn’t mean it has much more capacity due to the oddities of how the refrigeration cycle works. It’s more about the size of the space and the heat coming in than anything. Even a walk-in freezer that keeps food well below freezing (think -10F or -23C) may only need 10,000 BTU/hr capacity, which is no bigger than a medium sized window a/c. The difference is that the coils are going to be larger, with special defrost circuits, receivers, accumulators, and particular metering devices and pipe sizes designed specifically for those conditions.
You skipped over the part about adding a valved connection for the refrigerant (not easy to find except at an HVAC supply) and hooking up a vacuum pump and gauges to evacuate the piping and then fill the lines with the proper amount of the correct refrigerant. Did you have the equipment to do that yourself or hire an HVAC pro? I could do it because I have all that stuff but an average person certainly cannot. Cutting the lines in the first place was illegal unless the unit had no refrigerant in it. I know it wouldn’t bother a lot of people but we do have many environmentally concerned folks here.