This is a good example of why umpires are taught to be rule book experts without being rule book lawyers.
In NFHS, a batter can not permit the pitch to hit them. Like any other judgment call, its umpire discretion. However; the spirit of the rule is not to reward pitchers for throwing 2 feet inside, it’s to dissuade children/minors from putting themselves at risk of harm to get a base when they could easily have gotten out of the way.
A fastball is almost always going to be awarded first bc the reaction time needed to process the pitch and intentionally decide to not move is not there, a slow baby curve is another story.
The best saying I’ve heard is to ask myself, did the pitch hit the batter or did the batter hit into the pitch? Too many coaches want to beg for no base award instead of teaching their pitcher how to locate their pitches.