A swamp cooler is designed to cool your space on the cheap. I don’t know how one can be used to grow MJ. I would think the plants would need heat rather cold air circulating. They will provide lots of moisture, 'though.
In case anyone is wondering-a swamp cooler is a homemade, redneck, hillbilly kind of air conditioner and yes, they work.
Now, if I sell my car and it is used in a crime, then I am not culpable unless I have full knowledge of the crime or intent. However, ask your confessor.