Your iPhone camera photo is in three-point perspective. Three point perspective is a view were you can see perspective in three directions. So there are three vanishing points. there are no parallel vertical lines. The vertical lines also point to a third vanishing point. In the next example the third vanishing point is underneath, because the view is from above.
3-point-perspective, wikimedia:
So if you didn’t edit your iPhone photo, it should work. The third vanishing point in your photo is above:
edit: If you have a picture with parallel vertical lines (2-point-perspective), taken straight out of a ‘conventional’ camera, it will also give a good result, for the ‘principal point’ is in exactly in the center of the image.
Here is the manual for Match Photo:
This manual is very clear, I think.
I wish you every success with your project.