Stories like these give CNC a bad name. I also feel bad for him. There are unscrupulous people everywhere, especially on online marketplaces. That is why I always advocate for getting stuff directly from the manufacturer. At the end, they may be expensive - but infinitely better. You get your peace of mind and much better attention for your problems. At the end of the day, cheap is expensive.
Whatever happened here is not in any way unique to the CNC business. Scores of people out there are just waiting to con others their hard earned money. It so unfortunate that something like that happened to you.