You can share Panopto recordings by sharing Panopto course folders. Folders can be shared with people not enrolled in the course, such as teaching assistants, colleagues, and anyone outside UW. All Canvas permissions and courses are copied to Panopto, so there is no need to add people already in your Canvas course.
To share a Panopto course folder, you add people to the corresponding Canvas course. Learn how to add people to your Canvas course: http://guides.instructure.com/m/4152/l/55482-how-do-i-add-observers-and-tas-to-my-course.
Don't use Canvas? See Share Recordings in Panopto.