According to NCAA rules an offer can not be made until a student-athlete is a senior. A coach can verbally say whatever they want, but are not bound to what they say. Only the National Letter of Intent binds a coach to give athletic money.
Are you serious??? Is this your first day? What you say is technically correct. However, a verbal offer can be made at any time and at any age. Yes they are not legally binding. However, typically in softball, the verbal offer is honored by both parties. In fact, in most cases other coaches honor them as well and quit recruiting.
It's always cute when parents of younger age players come on and quote rules.