There are illegally made full auto weapons out there. I seriously doubt this clown had one. But they do exist. Clever people can convert the semi auto ones to full auto.
Back in the early eighties and the seventies, you could mail order parts to convert practically anything into full auto. There are still some of those parts floating around, and there are people with enough skill to duplicate these parts in their garage.
And the semi-auto Kalashnikovs that you can buy practically everywhere outside California are very easy to convert. Please, just take my word on it.
Still, my money says semi-auto AK or SKS.