if it is not seen in the privacy settings then the app would not have access to the photos. I would try uninstalling and reinstalling the app. during the setup it should ask if you will allow it to access your photos.
No luck, maybe the current update of IOS is not compatible with the application since the last update of the app was 2 years ago. Sad that Sandisk did not make any update or support afterwards. Thank you for the help though.