First, it depends on how selective the college is. If the admission rate is more than 30% and your son has a pretty good chance of getting in, your questions (and their answers) will be different than if admission rate is 10%.
These are good threads for this question:
https://community.hsbaseballwe...ir-level-of-interest
https://community.hsbaseballwe...34#52687313962323334
At super-selective schools, if the coach really wants your son, he will probably tell you up front (i.e. before you ask) what he is offering: something like "I have 6 names that I can send to admissions with a 99% guarantee, and yours is one of them." That is different from "I send a list to admissions and you will be on it but ultimately it is up to them, but if you get in I would love to have you on the team" which is different from "I don't have a slot for you/room on my list, but if you get in on your own you have a place on the team." Whichever you get, you can ask "what percentage of kids with this support do get in?" They know that you get one shot at ED, so they should understand.
Note that most will ask you where else you are looking, you should tell them, they all know each other and probably already know the answer.
At less-selective schools where your son could easily get in (possibly with merit money), the "offer" is different, and, as others have said means less.