If it's true that having visceral fat mass of > 0 is a risk factor for metabolic syndrome, then you have A risk factor. But since you are negative on all other measured risk factors, you do not have the disease itself.

A similar example. I have a grandmother, two aunts, a sister and a cousin who have had breast cancer. I have a strong family history, thence, strong risk factors for breast cancer. But I, myself have not had it. And, the older I get, the less likely I am to get it: ALL of them had their first symptoms before the age of 50.

You have neatly eliminated all but one of the risk factors for metabolic syndrome. And that one is a guess.

MY guess is that it's about as accurate as assuming that total cholesterol greater than 200 is a risk factor for cardiovascular disease, and should be aggressively treated with statins. IOW: totally inaccurate, and based on further totally inaccurate assumptions about fat, in general.