Maybe because he had hired a marketing guy to write his own client testimonials?

From experience, when working with clients on case studies and testimonials the individual concerned will often talk to the marketing team and then the marketing team will transform their comments into something short and snappy for approval before publishing. Perhaps that’s what is meant by ‘writing testimonials’ in this case?

Sure, maybe he does, but if that's so then we should read that and respond. Down voting and flagging such a comment isn't helpful. It's not even an opinion people don't like, it's something that has happened, and, if true that's very relevant.