The sole can affect the MPF substantially. The amount of weight in the sole obviously influences the vertical center of gravity. The front to back radius of the sole design can also influence the vertical cg location with more radius, and more sole angle will drive the vertical cg number higher. Ralph wrote about the Fitting, Performance and Playability Factors of Wedges in chapter 12 (pages 466 to 526) of his book “Golf club Fitting and Performance, the Principles, Procedures and Playability Factors”. Too much information to try and put in this forum, but I would encourage you, or anyone, to read it to better understand the characteristics of wedges and how they perform. I will see if I can get it posted to the website.
As far as CNC milling, it is simply a way to precisely achieve a shape, or a spec. Sometimes it is done for cosmetic purposes as well. CNC milling of faces insures the faces are flat, which is important.