I'm skeptical about using the CCK and a USB splitter. Since the iPad already supplies some power to the CCK USB port, it seems unwise to try and back feed another power source to the same port. If someone has done this, and it works, I'm ok with it. But I would not do it myself without confirmation, or a pinout for the CCK (which I can't find).
A powered USB hub might work better, but I can't guarantee that would work. You would not (should not) use the camera connection kit in this setup. Just plug both the iPad and the keyboard into the same Hub. A newer hub might even provide enough power to charge the iPad at a reasonable rate, though probably not as fast as it's own charger. What the hub won't do is risk damage to the iPad or keyboard.