Pardon my lack of knowdlege on Fotoforensics. Their analysis confirms that it’s a real photo, right?
Were it photo shopped the analysis would show a discernible outline around the portion of the photo that was brought into the original photo’s background. In this case the homogeneous texture around both subjects infers that it is an original photo.
That is what I’ve learned from others here when it has been brought up before.