They can go investigate it! We just usually update locations at the end of the month when we do, so if your character wanders, feel free to just see general forest with lots of wards and stuff placed around the trees and have them have the bad luck of finding nothing super notable until the end of the month. In terms of life and spirits, it will be largely empty at this point. The stone giant will be a large monument, but ultimately seem to have just gone back to being nothing but a gargantuan statue. Attempts to dig into it will find that it seems impenetrable when it is not awake. Damage that was done while it was moving will still be visible.

Hope that helps!