If this student committed suicide because in his mind his lost self-esteem, as appears possible, do you really think laughing at him at the time of his anguish would deter him, I truly hope you are not a student advisor. I am anything but the touchy feely type of individual, but I attempt to assess completely the situation before embarking upon a course of action whether it be laughter, anger or whatever. Laughter may be called for when an other is contemplating a stupid stunt but wholly inappropriate with one who is suffering emotional anguish, whether or not such anguish is justified.
I wonder those trying to justify laughter i this case are trying to justify their boorish behavior. I can laugh as hard as any individual when someone succeeds in seeking the Darwin award, but this is not one of those cases.
Laughing at HIM at the time of his anguish would not be helpful, however, laughing at someone else who committed suicide WOULD help.