Jetpack tiled gallery linked to attachment no lightbox

Using a Jetpack tiled gallery in a sidebar with images linked to attachment. This then shows as I want but the image when clicked just displays in the browser with no lightbox. I have looked at some other lightbox plugins but they require a tag to be inserted on the post/page which I dont have access to.

https://photoclubmeteorite.patbell.co.uk/?attachment_id=494 is an example, i want to click on the image and see a closeable lightbox not a browser page I must back from or lose the whole website and have to go back in