It does not matter whether you are believed or not Dave. I do believe that it is highly unlikely that the scoring mechanism would be broken only for certain part of the test, and some of the time. However it does not really matter if you believe one way or the other. If you need to get across a river, complaining about how unfair it is that it sometimes gets too wild is useless. What you need to do is to think of a way to pass it, or give up your goal of getting to the other side.
Similarly, believing in that you are a victim of some uncontrollable factor will not fulfill anything. What you need is action. You could choose to contact them and request a re-grade by people, or gather some signatures and testimonies to raise a serious challenge to the validity of the GMAT score, or simply take the test again and prove your true level is really higher. Whatever you choose, you will be moving closer toward your goal. Believing yourself as a victim and complaining about the unfairness, on the other hand, do not move you closer.
There are many uncontrollable factors in the coming challenges of the business world. If you are planning to enter this world, then you need to prepare youself to face the challenges, and be ready to prove yourself with your action.