Disclaimer: I'm a proponent of using whatever is interesting to young people to hook them on the field of data science and analytics.
Find the applied mathematics program and campus culture that gets him excited the most, and has a club baseball team. Develop the analytical thinking skills, and the data production skills (python, R, SQL, Tensorflow) for a career getting paid excellent money for thinking up and answering awesome questions about anything he is curious about.
And play club baseball to stay connected to the game, and become BMOC on the internet by contributing quant-driven analysis of awesome new talent
. I doubt any baseball program would turn away a student with interesting questions and a willingness/ability to apply data toward answering them. Or maybe they would... not all baseball programs are enlightened... probably wouldn't want to compile that program's stats, anyway.
Applied mathematics - the great analytics people I work with come from all kinds of applied mathematics backgrounds. Electrical engineering, political science, computer science, physics. I can think of just one who came out of a business program. For someone starting out in their career, I would be wary of "data science" programs cropping up everywhere.