The people who determined that amphicyonids are a separate family within the order Carnivora are competent anatomists. Features of the auditory bulla are distinctive between different carnivoran families, and amphicyonids are different from any extant families. I note that you are now claiming that the Order Carnivora is a single ‘kind’. Why not just call all placental mammals a single ‘kind’? That would fit well with your declaration that all marsupials are a single ‘kind’.