Update: well the queen got shot. I put the two ring leaders in disguise amoungst the NPCs one polymorphed to look like a human camera boy, the other as a highstanding member of their order who always wears full armor, giving them a few quirks and dropping a number of stuble tells as well as gaps in knowledge. I placed some side quests like getting a bottle of wine in the kitchen with their favorite npcs that I knew they were likely to want to go speak with where clues could be found, the only clue they found was as one poster suggested have them fetch a part for their resident mechanic who was workng on his latest invention and they overheard whispers in the vent talking about waiting for a cue from "boy-o" and "funny armor guy" while making humorous remarks at their disguises, the pc however missed the opportunity to flush them out of the vent with steam for interrogation and kept the information largly to himself only telling 2 other party members of the plot he overheard. The hint was mostly unacted upon, they first grilled the armored ring leader immediately accusing him of being suspicious. Him being a barbarian with low CHA and knowing nothing about the monster hunting organization or about the person he was disguised as other than that they were supposedly stationed in turkey, simply kept denying the suspicion and avoiding questions while throwing claims of suspicion back at the party much like how an evasive toddler argues and tries to hide things lol, answering any questions about himself with real details of his past (a favorite npc is a friend of the real black knight and could have denied the legitimacy of his past, he even told them to send them his way at the beginning lol) giving both his backstory and avoiding making any untrained bluff checks. Sadly no checks were make to pierce his disguise or read his motives, before another PC moved in and suggested they stop pestering him. The photographer however is someone they know well and worked with for a time, a sadistic and manipulative teifling who despises humans snd high society, he liked to pick on the human in the party calling him "pinky", and sarcastically exclaimed that they were his "favorite" because they came from a rich family. He acted as the party's excruciatingly clingy fan boy with an eerily simular voice and gushed over the party whom are mostly unknown to most common people, revealing that he knew far too many details about them and going as far as to telling the human that he was his "favorite". However one by one the party passed off the annoying fan boy telling him to keep an eye out for anything "suspicious" (I kept pestering them about specifying what was going on in an attempt to make them say outload amongst the crowd there was going to be a terrorist attack, even making the leap in logic myself when they tried to keep him in the dark and running with it as if he had connected the dots, none of them picked up that nobody else but the teifling knew the party was put in charge of fighting the terrorists) until he reached the monk. Our LE monk who is on a zealots quest to end evil without caring about the morality of her methods is the most suspicious but also the most blissfully ignorant as to what constitutes as evil. She immediately immediately told the photographer that the best way to test if someone was suspicious is to punch them and see if they react as someone trying not to raise suspicion would reactly calmly in an attempt to act remain natural. After some prying to get information out of them as to who to punch and more subtle displays of the gaps in the npcs knowledge I made another leap in logic in his favor exclaiming that if you want to hide you should do so where it's least expected and right under the nose where you can observe everything, pointing to the queen as the perfect suspect and asking aloud if he should punch the queen. The monk agreed and suggested aloud for the surrounding nobles to hear that he pretend to take her picture before running up to deliver a sucker punch. The party began making their way toward the throne to check on the queen just in time for them to see the photographer approach with his camera and fire the rifle concealed in the camera at the queen just as he planned. My party has been kicking themselves for hours
