This solution below shows the connection line paths of the 6730 classic camera button switch. You can use it for troubleshooting the camera switch problem.
If encountered and try to to fix this such problem, you may first check the camera switch assembly for possible damaged, then replace it if found already faulty.
Nokia 6730c Camera Button Switch Connection Tracks
You may check and trace the camera connection line paths as shown above, you can also use it in finding a spot where to apply an alternative jumper wire if the switch PCB solder pads is already lifted.
The button switch is also associated or being connected to some of the numeric keypad keys. If there are certain keys that is not responsive also including the camera button switch, the problem may possibly lies on the keypad filter IC's.
By replacing it only fix the nokia 6730c camera button switch problem.