Yes, there might be a reason for Simonds' generosity.

But that implied that he knew fairly well what John Mark himself half guessed.

The thought that she was under the suspicion of Mark himself was terrible to her.
She drew a long breath and advanced courageously into the gaming rooms.
The first thing she saw was Fernand hurrying a late comer toward the tables, laughing and chatting as he went.

She shuddered at the sight of him.

It was strange that he, who had, a moment before, in the very cellar of that house, been working to bring about the death of two men, should now be immaculate, self-possessed.
A step farther and she saw John Mark sitting at a console table, with his back to the room and a cup of tea before him.