Seishi Yokomizo is the pinnacle of Japanese reasoning. But I still can't help reasoning about the defects of the novel. Because the development of mystery novels has gone astray. It is often emphasized that human reasoning is used to explain all mysteries. The murderer tried to design a perfect crime. The design itself is actually full of loopholes.
Real cops, detectives, that's not how they handle cases. And fictional things, there will always be loopholes. Keigo Higashino, now known as the great god of reasoning, is full of loopholes in his highest work Bai Yexing.
So let it go. Those loopholes are either intentional or poorly conceived by the author. Mystery novels are basically novellas, and Holmes has enough space. Written in a long story, there are inevitably flaws.