If you really want the single tracker to show up at the top like that without being in a group on the page, I think you’d have to basically create a “virtual” tracker and manage it yourself.
Check out this dicuscussion for one example. That uses an input_boolean and automation, but you could probably also use a template binary sensor with the class set to “occupancy” to achieve similar results, depending on the behavior you want.
For the gravatar image, I think you’ll have to customize the virtual sensor and add the entity_picture. You can get the URL from the attributes of your existing tracker.