When a page hangs several times in the menu, it is always the last added in a kañooh structure (main navigation, footer navigation and disclaimer menu, so no self-created) being used. So if you want another bread crumb, you must put it in the last place. In the example, Footernavigation - Contact is created first and Main Navigation - Contact (the dominant) last. To show in the back-end which one is used, there is now a text behind the dominant.
The dominant breadcrumb is always used except when you go to the page via other navigation (here in the main navigation example - About Us> Contact and Foot Navigation - Contact)