He needs to email (a lot of) coaches and get on their radar.
It’s really hard to add much without an idea of level of swimming, but I guessing ASU and Purdue are way too fast. My guess is that both have strong active club programs.
OP, has he gone on swimcloud and filtered by major?
ETA: the challenge is that a lot of great engineering schools are also fast.
From swimcloud: schools with 50%+ acceptance rate and AE majors - slowest to fastest
University of Buffalo
WV Tech - NAIA
Clarkson - D3
Illinois Tech - D3
WPI (great school) - D3
RPI (also great) - D3
Rowan - D3
Florida Tech - D2
St Louis University - D1
Missouri Tech - D2
(The rest get into pretty fast territory ~T50 D1)
WV University
University of Cincinnati
Penn State
Purdue
U of SC
U of Arizona
U of Minnesota
U of Alabama
Texas A&M
Ohio State
Virginia Tech
Auburn
U of Tennessee
Arizona State