The 2009 model Bushnell Trophy Trail camera has a small 3/16 hole to padlock the door to the camera. Suggest mounting in a metal "bear box" and lag bolting to the tree. The "bear box" is padlockable.
The Moultrie Game Spy D55-IR has 4 each 3/16 holes (one at each corner). The door is also padlockable. Cable wrapping around the camera or (installing in a bear box would be better).
Spy Point IRB has 4 each 3/8 holes in the back corners of the camera. The door is also padlockable. A "bear box' would further increase security.
Increased security keeps honest people honest. If thieves want something bad enough they will find a way to get it, or destroy it in the process.
jrbsr: I realize you are trying to prevent theft. In your picture, all one has to do is snap or cut the plastic padlock latch on the camera. A "bear box" would offer more protection, along with your cable lock assembly.