I haven't made any video about it. You are right, when you refer somebody in your own office or company(this person can be your colleagues or even your boss ) to your customer, then you should not use .. SAN , because you must speak in humidity manner
It means you and all whom you belong to, you speak humid way ( kenjougo謙譲語)without SAN, neither SAMA , only family name , when you refer these persons to your customer