Given Chen Yan's personality and his insistence on being where the action is, he definitely would have noticed if they had done anything to draw attention.
But his answer at the time was that nothing had happened...
And yet, that evening, Ironman—who had supposedly done nothing—produced a note from Shui Qianliu.
From this, two possibilities could be deduced.
The first was that Shui Qianliu and Ironman were working together.
The second... was that Shui Qianliu had fallen into Ironman's hands.
Considering Ironman's obvious intent to frame someone, the former was unlikely.
Therefore, it was highly probable that Shui Qianliu had been tricked by Ironman.
That was why Fang Shuwen didn't expose him, but decided to play along.
He just needed to follow Ironman's script to figure out what the man was truly after. He might even get the chance to follow the trail and find Shui Qianliu.
So when Fang Shuwen and his party arrived in the withered woods, he was acting the entire time.
