回複：EB1b-I140 RFE(NSC), please help, 小白兔, Thanks!

I ran into exactly the same problem.

This letter is extremely important because my case was denied solely due to the same reason (working at University, NSC, EB1b, denied on 3/6/2006). I got similar RFE, but my lawyer misunderstood it and my case was denied. Actually the letter should be the copy of the official job offer letter. So, it should be a letter to you rather than to NSC. If you like, you can also send a letter to NSC either from your department or school (It does not matter who signed it), but it is the offial job letter that USCIS is asked for.