Is it possible that more people can be cross-trained on sandwiches, perhaps? I know I'm probably just speaking out of ignorance here, but back when I worked at theme parks (especially in restaurants), everyone essentially was cross-trained in multiple stations so that even if one person called in from work, everyone would still know what to do.
It's really only a problem when cooks call in from work because other cooks have to take over, and this is only a bigger problem when you have a small kitchen staff, so people would have to rely on front-line peeps who are trained on kitchen material, which is not too common to find, haha. u_u