Hello amcleod,You can load the coordinate information for the camera locations to the Reference pane from the CSV/TXT file using Import button on the Reference pane toolbar. The input file should contain the image filename, x, y and z coordinate.
Andy,maybe you should check if your camera ids are identical between reference pane and csv file. For example if in reference pane your first camera id is DJI_0001.JPG then same entry should be present in your csv import file...