This doesn't seem to be about showing exorcisms per se, but more about following the exorcist as he travels the world to meet his 'patients'.
From the FAQ:
Q: Does the film include a ritual performed by Padre Jose Antonio Fortea?
A: The film does not include footage of an exorcism performed by José Antonio Fortea. We show him as a major star and a speaker, as well as a person who performs liberation masses, where people fall to the ground and act out a state of demonic possession. He also performs a trial-exorcism on Constanza behind closed doors.