'Al-Jawf' is just another name for the city Sakakah. E.g. its university and airport is named such. On some maps you could see a place near Sakakah which is named 'Al-Jawf'. But actually it's the ruin and oasis named 'Dumat Al-Jandal'. Confusingly Sakakah is the capital of a province named 'Al-Jawf'.
Forget Googlemap, it just shows empty desert in the south of Sakakah. The only detailed map I found suggested the city 'Huj'. The name of the city is like the other names of settlements on this map not correctly transcripted. I was not able to find anything with google. You may have some more luck.