Just another twist, it does not matter if there are 100 coaches if they are not the coaches of the schools where your son is interested in playing!
Our experience with Dynamic events (playing on a highly recruited team) echoes the above, but keep in mind, the coaches there are mostly regional. We did Dynamic events in VA, MD, NC and the list slightly varied -- when in MD we had schools like MD, UMBC, Catholic, GW, Georgetown and more who were for the most part not in NC or VA but also the same Liberty, Radford, VCU, VMI, Richmond, Va Tech, JMU and such were at most of the events, while in NC we had High Point, Wake, Elon and more who did not necessarily make it to MD. My list is not complete, just trying to give you a sense of who was there the past few years.