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'Cameras have been installed.' is a passive construction. The cameras didn't do anything. They were passive. Someone did something to them, namely: installed them.
'Cameras shall have been installed.' is a Future Tense passive construction. At an, here undefined, point in the future, the cameras will have been installed. Again, the cameras are (to become) the passive objects of someone else's action, namely: of the technician who will install them.
'Cameras were to have been installed.' is a subjunctive (were = hubiese) passive construction: no cameras have been installed. This is the declaration of an unfulfilled intention. The intention to install cameras was in the past, but no action has occurred, and as such cannot correctly be termed Past Passive Infinitive. The same goes for Rover's examples.