Yes you can go on the roof. Since yours is 6 years or so old I would carefully explore for soft areas while on hands and knees. Avoid shoes that can damage roof material. If you find a soft area you may have water damage. Lots of posts on this. Your manual recommends inspections of all vents and seams, etc. a couple times a year to prevent leaks and damage. Lots of posts on this in the search bar above. Just take care to avoid a fall.
2017 SLX 195RB
2021 Jeep Grand Cherokee Summit L 5.7L V8
Andersen WDH hitch, Renogy 100 AH Lithium &
200 Watts solar panels from Renogy
Prev. '14 Jeep Grand Cherokee Overland, gas 3.6 V6