NOTE: Currently on Mac OS, the silent installation will fail with the full-product .dmg file. You must use the standard web installer to "Download without Installing" in order to acquire a set of offline installation files that can be used in silent mode.
I have the same problem and Mathworks are not able to answer the question. They made some changes to silent installation and there is no documentation about this. I belive that they don't know niether how to do!!!!!