It's not about the picture itself, it's about what RDM himself said about it. Recently he again confirmed this to Maureen Ryan, in email "none of the people in the final supper picture is the final Cylon".
It doesn't require folding the picture or go over all the little details in the picture to find out what that means, does it? It's pretty straightforward: who is on the picture, is not the final Cylon.
So, do you think that Ron Moore is not serious (lying, in other words) when he writes this?