I guess the point is not the corretness of information in KYC but the fact that you organized duly the process of KYC monitoring. So if one day the police comes to you, as responsible for KYC, and asks questions about a John Smith you can show the documents you have. You are to do your part of business. But there are some good services there that can make a pretty good job in verifying peoples passports remotely. They can say if the papers are fake or not