So, I'm grasping at straws a little, but I can see some sort of logic... I would say that
is the right way to fill in the blanks. I feel like you need the を somewhere if the 写真 isn't being 撮る’d. So why is the 猿が子供を育てているところ is being 撮る’d in my suggestion?
To explain that, I think it's helpful to view the とる family of ...