I think this works as a decisive moment. However, this falls a little short in terms of impact for me.

The lighting feels rather flat... But more importantly the expression on the face doesn't really speak to me... I wonder if there was another moment during this session where we could really see some trepidation on his face. That might sell it a little more.

Gettings his hair cut for a good cause. I don't quite feel the decisive thing, though his expression is good.

I really like the story behind this photo. And I love the resolute expression on the man's face. I suspected the story behind the photo from the thumbnail, but even full sized you have to look around a bit for confirmation. If you could have presented the shot so more t-shirt was visible, or a sign was in the background, that would have enhanced the story telling. It would be nice to see all of the hand holding the clippers and you cut off one side of the hair. I like it over all, but some small technical bits interefere with the story telling.