I wonder how on earth this was filmed. I remember watching a film secretly made in another SE Asian country (can't remember which), which showed cats being kept in appalling conditions in cages, as many as 100 in a cage we would use for a single medium-sized dog, then pulled out one-by-one, dunked in boiling water, then skinned alive. While still alive the cooking process was commenced, and only after they had finally expired were they gutted. The whole process was designed to cause the maximum suffering for the animals even though it had no beneficial effect on the meat, and the film makers concluded that these people were deliberately trying to show that they despised animals and regarded them as nothing more than conveniences for their own aims and sadism.
The restaurant that this was going on at the back of was in a main tourist street, and tourists were shown sitting at tables, eating whatever. Either they really didn't know what was happening a few yards away and producing the most blood-curdling noises as the animals screamed in agony, or they knew or suspected but really didn't care.
The activity was technically illegal in that country though the police well know what was happening and did nothing to stop it, and the secret filmmakers were genuinely in fear of their lives as they were making it. The filmers were local nationals, as westerners would have been immediately suspect. On one occasion one of the kitchen staff suspected there was a camera, and the scene as the filmer ran off with his camera still running amply demonstrated the danger they put themselves in. They said that as well as avoiding detection by the restaurant staff they had to avoid the police, who would merely detain them long enough for the restaurant staff to catch up.
The film was broadcast on BBC TV maybe 25 years ago and there were a few days of vocal outrage, then people forgot. It's the main reason I've never wanted to visit that part of the world.