The photo mock-up was to show that a sunroof can be added to the rear as well.
If one looks carefully at an overview video, there does appear to a latch inside the SUV roof. Not finding any official spec or info describing or showing a removable panel in the SUV top. SLATE may or may not offer...
You have a good eye! It certainly does look like a removable panel from the inside. This may or may not become an optional or standard feature for rear SUV panels. Has anyone seen any official statements about such a feature?
Installing a sunroof requires cutting both the roof panel and the headliner. Core swap of just the roof panel (likely bonded to the frame) would not include the headliner. Aftermarket sunroofs are available professionally installed at local vehicle customizing shops nationwide.
Aftermarket sunroofs are always an option, for any vehicle. DONMAR has just the right fit for what you had in mind. We are in contact with Slate as well.