Doesn't the USD have a unique serial number associated with each bill? I'm sure when banks make in-transport transfers between entities, they know exactly which

Doesn't the USD have a unique serial number associated with each bill? I'm sure when banks make in-transport transfers between entities, they know exactly which series they are transporting, and if a robbery happen, they share those series that got stolen with the police. If the police makes some unrelated arrest and find a bunch of bills, they can probably trivially look up if that money have been involved in anything before that.