My sons last WWBA was attended by A LOT of coaches. I remember turning around during our first game and looking behind home plate and we counted 13 college coaches (snuck a picture to show my son later) and we were just two average teams by PG WWBA standards. Later in the tourney we played in the losers bracket 40 minutes away and there were still colleges attending. You will see a lot.
Best advice my son was given before any of these National events was to send out your schedule to the schools you are interested in about a week before the tourney, include a HS recap and some recent video if you have some. My son did this and we were surprised how many swung by.