The '07s already use the longer cam bolt.
Put a small amount of epoxy in the hole, screw the cam bolt in and adjust the height before the epoxy sets up. Make sure no epoxy gets on the cam lock knob. If it does, simply spin the knob every few minutes until the epoxy sets up so it will not bind the knob. That should do it. Although epoxy doesn't stick well to Polyethylene, it should give you enough "bite" to stabilize the bolt. Use a good marine epoxy.
The cam columns carry a lot of stress and are a weak link in the system -- drilling a hole would would be detrimental. Similarly, although Hobie makes a helicoil insert, I would not recommend it -- it adds additional stress to the cam column.