It should fit - I am playing around with grilles at the moment and have had the 2009 grille on a 2006 model.
The top holes align perfectly, the clips on the lower part of the grille don't align with the lugs on the bumper bar. You have to partially cut the clips on the lower part of the two bar grille - then you are left with a small gap between the lower part of the grille and the top of the bumper bar which you can fix with some black rubber channel. Hope that makes sense ?
I am not sure if that part no is the AMG grille as it has silver mesh and the two horizontal bars are also silver - I believe that the mesh on the AMG version is black and I think that the two bars may be black as well behind the chrome strips . I can't seem to find a good photo of a late model (post 2009) CLS AMG grille ......