GC through NIW or Perm EB2?

I have Ph.D degree in agronomy with completed courses in MS statistics (no degree yet), and I am doing research on education research. Some attorenys told me because my degree is not in the same field as I am working, so I am not eligible to apply for GC throught this Degree by EB2 perm, but another half attoreny told me it doesn't matter, only what I am doing is benificial to USA, then I am ok to apply for NIW or EB2 perm. If you have any experiences or suggestions, please help!!!! Thanks.

(1) Can I use my Ph.D apply for perm?

(2) Can I use my Ph.D. apply for NIW, I have 8 publications in USA + 3 in china plus two book chapters, and a lot of presentation, hopefully I can get some nice recommendation letters from DOE, and I will work Project from DOE soon. It satisfy the requirements of National Interets.