its easy and safest for the company to say "no". Anything that lessens their risk is a bonus for them. A written request and a written reply may have yielded a different result. You're wise to be concerned, Larry and I don't mean the following as a criticism, you have done as much as any reasonable person would be expected to do. I just point out I in my profession have often been told things by insurance companies that on closer reflection turn out to be a little different. A "Charter" in Insurance terms may have a more limited definition, then under the terms of a Captains license, such a a direct payment to the operator, or regularly offered vessel for hire. I just don't know, and unfortunately maybe no one really does until an accident happens and an insurance company disclaims coverage leading to a court case. If in fact your vessel was being operated with proper safety gear on board and in a reasonable manner, and not overburdened, I don't know what difference it makes that passage was won in a raffle.