It's not all about advancement and being educated on the level of an elite coach. Level II is not just about educating elite level coaches. Everyone of those coaches on your marathon (and potential 5k and 10k lists) were given athletes that were educated by a "lesser coach. Yes, the top notch coaches may not go through the program but every one of the athletes on the list had middle school, high school, and college coaches. I don't have to know what Salazer knows to do my job. But the Salazer's of our world owe a debt to their athlete's previous coaches. If all we had were a bunch of elite coaches then who would find/coach the guys, or for that matter the kids, that don't get the immediate elite coaching?
Every one of the athlete's coaches you listed were preceded by at least 3 coaches and I'd bet my USATF dues (for what that's worth) that they are quite glad that their coaches handled them correctly. It's about so much more than the end result. It's having consistent, correct, and appropriate coaching from middle school through post collegiate is key.
Maybe our fascination with elite coaches is creating a top heavy coaching hierarchy and is failing to address the real need: discovering and nurturing talents while keeping them away from the soccer pitch, basketball court, etc. in middle and high school. It's easy to polish off a near finished product.