Sonia,
You are exactly right.
As you stated, the bogey or truck tilts down 17 degrees when deployed in level flight. In the flare, your 767 is about 3-5 degrees nose up (for the discussion we'll pick 4 degrees).
That means the front wheels on the bogey are 13 degrees down when you are flaring 4 degrees nose up. Evidently the engineers want those wheels to touchdown first. If you peek at your gear, you may find a damper (shock absorber) that takes up some of the force of rotation as the bogey tries to slam the back wheels on the runway. Or, it may well be the act of landing the rear tires after the first takes some of the impact away from the landing. Either way, it is clearly by design.
Cheers!
PT