Idk what the slabs are usefull for because i didnt really read the part with alex but when i do the code on the page it just get me back and the only thing i can do is return or look around idk if its suppose to unlock something?
The slab is for inputting secret codes hidden around the game, the code on the piece of paper in the background is just for getting back the the alternate dimension verison of the village, it was part of the story. There will be more stuff to do over there soon.
