What if they have nothing to do with a the carmen vampire conspiracy and are just
Vampires are renfield types that just want be left alone and live out their lives without anatagonizing anyone. Its not like these servants are killing anyone or did anything wron, by informing Val Halan, he would slaughter everyone just for being vampires instead of killing in self defense.
Following his way is to genocide all vampires, regardless of whether , the vamps intend harm or just want to coexist.
[X] Hide the body in your room, clean vomit and blood, its better to do it yourself but if absolutely needed, as a last resort, get a couple of guards or trusted servants to do it, pay them then erase their memories discretely, take a bath and change clothes.
prepare a task , anything really just to keep the servants busy, something harmless and important, anything that can explain his or whatever his real names is dissapearance for a few days( this group contains 11 servants already checked and one dead servant) Get the puppy guy who is like a brother to you, who sucks at stabbing people in the back politics, whose name begin with letter A( forgot his name). Get him to work with you on coming up wit a excuse to make 11 servants and 1 dead one dissapear for a few days excuses can range from a paid vacation, filling in for some workers that are on strike, menial labor, cat stools they have to clean up, a training course in novel writing, or just winning a bet against a friend, any excuses that can take them far away and buy time. Don't tell him about your suspicion though, just tell him that you were attacked and you may have killed someone in self defense, regardless, you want to snoop around and you rather that the less people know about his dissapearance the better for a week at most. Do this before doing anything else, except for the clean up mess and bath bit.
send some of the servants of on some minor errands (it will buy time incase the dead mans friends, aquintances come looking for him) tell someone to prepare a minor party to celebrate something like finding the ledger or anything.
Do some thinking, maybe the person attacked out out desperation and panicked, knowing what kind of a person Val Halen is he probably ( correctly assumed) that he would be killed on the spot, moreso that he's not completely human. The others like him may or may not be connected with the conspiracy, You've seen Val Halan's face, he seems like a strong man, competent, caring and friendly has genuine care for Stirland and Sylvania but, on the otherside he is dangerous, callous capable of killing without hesitation, uncaring lof who he has to kill like the art troupe he mentioned that would go to the pyre or the asylum.
Whatever that thing is, you know nothing about his objectives, whether or not he is part of the Von Carmen conspiracy, whether they hurt anyone or not, whether they are even guilty of anything besides not being completely human or even if they have any ulterior motives besides living their life minding their own business and mostly whether they deserved to die or not. What you do know is that once they or Val Halan discovers what happened blood will be spilled, Val Halan will kill simply on the basis of not being completely human, they will probably panick and in the best case run away or try to kill as many before being killed themselves. Most of the time you did something for your boss, someone dies, You need more information and secrecy.
Armed yourself, ready yourself with a few defensive spells to use instantly and some spells that could help you capture someone alive, including the guy with superhuman reflexes. Get two greatswords as bodyguards. Make a pretense of interviewing 2 other people you already trust, at the very least make sure that the dead man isn't the last person being interviewed, before he mysteriously dissapear, and before you suddenly put a stop to the interview.
Prepare a torture room isolated.
Get the name of the dead man, confirm what he is , is he is a vampire, enchanced human ,servant? are there ways to quickly identifying others like him, without relying on complicated interviews, think about alternative ways to unmask them, maybe a spell that can reveal his nature. Or other subtle ways, like vampires don't have reflections, or the others like him maybe can't get drunk.
Do things secretly, if possible do your investigation without any witnesses that will know you are investigating something, dress as a newly hired maid, the two greatswords are just some men spending time with you trying to impress you. If necessary have some trusted associates distract any witnesses, when you investigate the man's room. Look for anything incriminating letters or anything.
The bodyguard will only stop tagging along only when, it becomes too suspicious for you to be with them when investigating, find out who his aquintances are, who he is friends with, what he has been doing, who he has been seeing, who his friends are, act as if he reminds you of a past boyfriend or something. Don't focus on him alone, ask about various handsome, strong and of some high status men, act like a airheaded, flirtatious girl who wants to marry like a fairytale princess. Don't focus on his associates alone, socialize with others not related to the case. Try to get a read on his associates, what kind of persons they are, normal, fake, plotting, uncaring deadly.
Select another interview room, cast some sort of enchantment beforehand that can restrain or capture others like him, that can be triggered at your command, prepare some defensive spells ready for you to unleashed, include some religious symbols hidden that may expose their true nature. Try to capture one or two so you can interrogate them, so you may have a chance to know what is going on serve Stirland without compromising your morals, and avert a bloodbath, and maybe deal with this crisis peacefully.
Try bluffing that you already know about the Von Carmen conspiracy and the dead man's confession. Make it look like you know whats going on, to get more information out of him/her and reduce chances of lying after interrogation depending on if he is connected with the conspiracy
A. If he is then , continue interrogation, plans motives, why he is helping the conspiracy in the first place who among the servants and guards are spies, tell him he will be imprisoned like a criminal charged wit a crime that does not merit death but imprisonment and live peacefully, and still keep his life, since you are reasonable and have no desire for violence and bloodshed, only the security of Stirland and its people, but if he remains uncooperative threaten to hand him over to Val Halan who is not only a threat to him but his friends. To convince him of your sincerity swear a oath to the gods that you are telling the truth when you want a peaceful ending where no one else dies. Use the dead man as a bluff about him confessing before he died. Use torture and other effective methods if needed. Regardless of information extracted.
Afterwards he is to be imprisoned indefinitely like criminals by the, makeup some story about him being a enemy of one of your contacts, or given one chance to collect his friends and leave this castle, and if ever he made you regret sparing him like killing other people, you will hunt him down and make him wish he was given to Val Halan. Whichever is the best solution.
B. If they are innocent try to learn more about their kind, try to get them to name others like them among the servants, its more of a precaution than bias thing, then they could either continue on with their lives as normal as long as they don't harm anyone ( use guards or spies to keep a eye on them) , or be allowed to leave the castle freely with their jobs reassigned elsewhere. If they choose to stay warn them about others that may not be as tolerant due to current circumstances.