Agree with above, but thought the question was would the camp at Vandy or Stanford be applicable to D3 player experience, not exposure for the camper. At D1 camps there can only be 1 D1 school in attendance, they fill the rest with D2s and D3 coaches. All the mass mailings will tell you we offer at camps, etc. blah blah blah.
Agree, be wise on how and where you spend money (Camps vs Showcases, etc. - they aren't required). I do think when you get older and Sophmore year/summer is the time to narrow down and start to visit campuses/coaches and programs. A 2025 has 2 more years before they need to worry about any of that....
However, back to the question, if you want to get a taste of what baseball will be like - you have to attend a sleep over camp like a Vandy or Stanford across multiple days. The 1-2 day camps won't give you a true glimpse of the rigors, the fatigue, the food, sleeping in a twin bed in a dorm, etc dealing with a roommate you don't know, that the multi-day 3+ camps will. (regardless of division).
Vandy was the most organized and well run camp of the lot, in our experience. We didn't go there to get any other exposure except to Tim Corbin, Vandy coaches, Vandy Campus, dorms and life as a college baseball player.
If you're shopping for exposure, Headfirst or the Academic Showcases are decent, but again not required. Those schools and Ivies will be at the big events, you just have to be on their radar and/or communicate with them to tell them where you'll be and when. Difficult with some coaches that don't publish who's pitching to give the scouts and recruiters notice (oh and the player too....).
Fingers crossed for the 22s and beyond they open camps and campuses back up next Summer.