It is not a question of whether we believe whether you were told what you say you were told. I think everyone here believes you. The pertinent question, however, is whether someone when completing a Global Entry application should list all countries that they have visited or some subset of all such countries. I certainly believe that you should list all countries that you have visited, without any exception for countries in which you did not have your passport stamped or otherwise create any documentation known to you. When filling out any government form asking a question, it generally is better to err on the side of being over-inclusive, as opposed to being under-inclusive. Unless, of course, you know what you are doing and why.