For this trophy you need to match all of the buttons at the same time as the bouncing ball hits them by pressing the corresponding button without making a single mistake. After each section in the boss battle, you will have to mash one of the shape buttons (whichever shows up). If you make a mistake, just exit and restart the level. For doing the boss levels to get the co-op trophy, make sure your second controller is turned on, wait till the last button-mash and press on the second controller to join. Then mash the button that is showing on both controllers. If you defeat every boss without making a mistake, the trophy should pop up after you defeat the last boss.