[Don't mind Akechi just holding up a photo of the head wound. The injury is barely bloody, and looks new.]

A minor correction, Archus-san's head wound was sustained post-mortem, most likely when he fell into the tank.

More significantly, losing a small piece of gold rope beneath a drawer would be easy to miss while dragging an unconscious person, don't you agree? Particularly if they were in a hurry to clean up the more obvious signs of their presence and return to their room.