The criminals are becoming so good at impersonating, how are you going to get around this? The only way is to have an independent system that goes back to the source and asks, "are you OK with this" as we as humans can be fooled.
At CyberBUND, this is what we are working on starting with your Xero accounting system in anytime you change something, an email is sent asking the client or supplier are they OK with the change. Simple but effective as now the criminal must intercept this communication as well, but once we catch one bad change, we know it instantly for the next one who is on our system. #cybersecurity