Decent story lines can absolutely be written for characters who are in for a limited amount of time, provided, of course, that the writer has the interest in planning and utilizing the time they have the actress instead of leaving her on the back burner for a huge chunk of her return time and then remembering, a week before she leaves, that he needs to write her out somehow.
I'm keeping my fingers crossed that, after Nik sits vigil at her bedside, she comes to and her first word is "Ric?"