This page of the guide to Resident Evil Village contains the solution to the mini-puzzle you may be interested in after finding the Treasure Map in the Attic of the Dimitrescu Castle. The following instructions explain where the treasure from the map is hidden, how to get to it, and what its value is.
Attic Treasure Map
You can find the Treasure Map when you get to the Attic. This happens right after you solve the five bell puzzle, which we described on a separate page in this section. The map's location is shown in picture 1, and the drawing is shown in picture 2.
Finding the treasure from the map
The drawing from the map points to the Dungeon you went through earlier in the game. However, Ethan could not reach the treasure at that time because he didn't have the Iron Insignia Key yet.
The dungeon is on level B1 and you can get there from the Kitchen adjacent to the main lobby. Expect encounters with singular monsters along the way. You must use the Iron Insignia Key to open the gate in the northeast corner of the dungeon.
In the new room, there is a Crumbling Wall (marked with an icon on the map). It is shown in the picture and you must use the Pipe Bomb to destroy it.
Tearing down the wall will allow you to reach the loot, but more importantly, you can now light up one of the braziers that hang from the chains. To do so, you need to swing it towards the hole in the wall.
That's not all - you need to light the second brazier as well. Both objects are quite far away from one another and unfortunately stop swinging quite soon. The solution here is to fire your gun at an inactive brazier and quickly push the already burning one towards it. The desired end result is shown in the picture above - both braziers must be burning.
You can now examine the sarcophagus. Inside, you will find the Treasure Azure Eye. It is worth noting that it is part of a set(marked as Combinale in the eye description). You should not sell it until you complete the set, which will create a single, more valuable item.