The case: Couple things come to mind. Trump never caries, or even has close by, anything that resembles a briefcase for his own use. In all of SloJoe’s time I’ve never spotted anyone remotely resembling a normal “fullback.” The fullbacks always have a bearing/manner/style all their own. And nobody screws with them. They get up/down and on/off by themselves. And the football is not in an overstuffed, overworked lawyer, type of briefcase.
Mixing the type of vehicle with the guy and the case it seems likely there is a football nearby.