Tamara's Hidden Tabernacle

The room to the right of the stairs (Tamara’s room) also yields some interesting information, even though this is purely an optional investigation:

• An ugly doll by the side of the bed.
• A letter to Tamara on a sideboard, which can be read to give you clues to her background and whereabouts.
• Incense and an old rusty key can be found in a wardrobe here, too.

Find the incense and old rusty key in the wardrobe in Tamara’s chamber. When you wish to follow the scent of saffron, use your Witcher Senses to see the misty odor, and follow it down the stairs. This eventually leads down to a gloomy basement. You must maneuver between sacks of goods and grain to reveal a secretly-prepared shrine to the Eternal Fire, a religious sect famous for their hatred of mages. Examine the bowl with burning coal if you wish. There is also a prayer, seemingly written by Tamara.

There’s another optional area to explore too. Inside the dining room where you first spoke with the Baron is a letter revealing Nilfgaardian demands on the Baron, as well as a few guards exhibiting just the right amount of contempt for your kind.