U.S. citizens visiting Shanghai Disney from either Tokyo or the U.S.

My family and I are U.S. citizens and we want to visit all the Disney parks in Asia during a single trip (Tokyo, Shanghai and Hong Kong). We are also airline employees who plan to fly standby on the long-haul flight either from the U.S. to Tokyo then onto Shanghai or standby directly from the U.S. to Shanghai... For either scenario is it possible to use the 144 hour Visa-free transit and visit Shanghai Disney if we purchase a confirmed ticket in advance from Shanghai to either Hong Kong or Tokyo afterwards?