If the recording was made outside of Panopto, for example Zoom, it is possible to upload them to Panopto. These recordings will not get their own window for the webcam as this is usually not made as its own stream. Zoom will embed the webcam footage directly in the screen recording.
On Windows computers Zoom recordings are normally placed in Documents\Zoom on the computer the recording was recorded on.
See Panopto's guide to upload video to Panopto.