Ive heard that the Japanese carriers lost at Midway, at least some of them, were still carrying the film taken during Pearl Harbor!
I too have heard that film of Pearl Harbor attack taken by their individual air groups went down with them. As none of the 4 had returned to ports in Japan, it is very possible that they did. And I believe that Cdr Fuchida may be the source of this and as the commander of the air group strike force, he would know.