When he was told that there was not yet any material, Aberbach decided to lock the songwriters in the room, by blocking the door with a sofa, and informed them that they would not leave the room until they had created the material.
Aberbach decided to lock the songwriters in the room. This was by blocking the door with a sofa. They would not leave the room. This was what Aberbach informed them. They had created the material. There was not yet any material. This was what he was told.