Ok, was this photo uploaded before or after the plugin was installed? By default WordPress doesn't import location data, the plugin enables that. So location won't be shown for images uploaded before the plugin was active.
If that's the case and it's only a few images you can reupload them to WordPress and if the plugin is active it will save location data too. If it's too many images to do that you can probably use the Regenerate Thumbnails plugin to regenerate the image metadata. Typically this plugin is for making new thumbnails after the image size settings are changed, but I believe while doing that it will resave the metadata.