This one time I ran a murder mystery without knowing who did it. I put in three butlers, each more guilty than the last. But the players kept poking around the bed with the body on it and asking awkward questions, so in the end, the bed did it
I wanna talk about this in good faith for a minute, because there's something of value here, for a lot of games. This is not a bit.
Bottom line, if you're gonna make a habit of doing this, please be open with your players and communicate your expectations back and forth.