Then why do you keep brining up the photo if you're not using it as evidence?
I mentioned the photo once, and it was in description of Mr. Clifton's actions at the scene. Mr. Clifton presents direct corroboration of the experiment through testimony and photography.
I'm not obligated to travel across country to find the photo because we already have his direct writen testimony on the matter. The photograph is supplementary to the case. While we do not have it on hand we know it exists and was published because there are numerous references to it in various literary sources.
But if you really have delusional doubts about the facts, you are always free to look at the photo for yourself. You know where to find it. You are also free to dig up the grave of Samuel Birley Rowbotham if you have doubts that he existed as well.
Rowbotham died in 1884. Lady Blount's photo was taken in 1904. How does Rowbotham peer review Lady Blount's work from the grave?
The experiments exist as peer reviews and corroborations of each other because academia transcends individual lifespans. In an article about Rowbotham's experiments Lady Blount's trials could be listed as a corroborating work, and in an article about Lady Blount's trials a reference to Rowbotham's trials could be listed as a corroborating work.
The convexity experiments conducted by these independent researchers produce the same undeniable result each and every time the experiment is performed: The earth is flat.