How often is she recording other sources onto cassette tapes? If never, she doesn't need the output to the tape deck.
While the preouts would work for that purpose, they're downstream from the volume control, so the signal would be lower than that of an unattenuated "record/out" tape loop output. To get the preouts to the same voltage would require cranking the volume high enough, which would probably preclude actually monitoring the recording with the speakers, as that would also be enough to drive the amp to full power and be screaming loud.