I am not really sure of the point you are trying to make. What you see in a player, is not necessarily what a college coach is looking for. As far as getting signed at a particular place, there are many , many factors involved for college, not just ability, but grades, test scores and overall character, team committment,etc.
Don't send your son to a showcase if he is not ready. And parents should understand that being invited back to a showcase means $$$, not necessarily because they had great talent. It is what it is.
The growing process of a player can be a complex one. Sometimes you need to be in the right place at the right time, but generally, a parent needs to figure out what would be the best venue for exposure for their son. We relied heavily on travel summer ball and team competition, rather than individual showcases. My my son was lucky, while he had talent, he had a great GPA, which brought his stock up higher.