When it comes to ID camps where 3-4 different college coaches are at, its is just luck of the draw which group the players are placed in? My son attended their first ID camp and was coached in a group by a different college than he was interested in. He did introduce himeself to all the coaches after but the one that he was very interested in did not see him play.
Usually random. What you can do to maximize the likelihood of being seen by preferred coach is to communicate with the coach in advance, let them know you are attending and very interested in working with that coach during camp and in learning more about the program and its needs. That way, a coach can try to get you in their group or at least make an effort to see you.