As I understand it, the hint about the role of the deceased refers to the fact that he locked himself in his room with a lot of locks. If that's the case,
then maybe he is
Count Redcliff. He violated an incredible number of laws of the kingdom, mostly accused of conducting torture and massacres of the civilian population in his lands. He joined the conspirators, relying on the prince's promise to forgive him for his misdeeds.
He seems to have something to fear.
If there's a murder, there should be a clue about the killer that needs to be matched with profiles or descriptions, right? And where is it, what should I look for?
And also, are the events in the newspaper given in the order of turns, or not?