I'm sorry to re-open an old thread.
I've the same problem. But here, the thread till now concludes that the issue was resolved by putting the accessor name of the VL b/w level 1 & 2 (the name in the Destination VO accessor name in View Link Properties). But i've even made sure this part. Still i'm having the above mentioned problem.
I've also raised a separate thread for the same. https://forums.oracle.com/thread/2563897