Could be a difference in definition/interpretation of the term crying- quiet teary-eyed vs. bawling.
Also, if true- he may not have realized he was noticed and thought he did a better job of hiding being upset, and is therefore, maybe not lying.
There are a bunch of different ways this event could have transpired- let it go. Let him feel and handle his emotions in the best way for him, because it really doesn't matter what you think he should do.
