"The real issue here is superheat, you will not be able to cool the compressor. When your wort is near boil temp and you start your refrigeration system your suction (evap pressure) will blow the valves out of the compressor. If you are going to go ahead and try it video your adventure from at least 10' back."
The above statement isn't necessarily true. If his uncle is into refrigeration and knows his stuff. He will install a back pressure regulator. Maybe a pressure limiting TXV, maybe a suction accumulator and oil seperator. Then, maybe he will liquid inject the compressor using a de-superheating expansion valve to cool the heads. However, if the guy is an appliance repair type guy. Using a condensing unit gutted out of the family Maytag or the lettuce cooler in Taco Bell. Then, hooks a copper coil to it. Then yes, I'd say you are quite correct...Not only can the valves be damaged. Much worse, the fusite can blow out of the side of the compressor, catching the oil on fire. Burning down the house. It's best to stay away from Rube Goldberg designs..... Like the one on More Beer. It's evident that the guy has absolutely no knowledge of refrigeration. Except, that when he opens the refrigerator, the kids orange juice is cold.