If he hadn't then Saft would have known for certain something was amiss with her servant's wellbeing. Seeing Rider so tense and serious as of late didn't sit well with her.

But as Iskandar yells loudly, she inwardly squirms. This plan of hers wasn't going to work if Rider lets everyone know their position.

...

As she prepares herself to suddenly be attacked she glances around confused. Nothing. She would have thought at least something would have come about from Rider's loud voice. Even an explosion or two from one of the other servants charging through the forest having to make it past her array of fire-seals.

"...Rider, Are you sensing anything?"