Garner went 13-of-17 from the field.
Jamal Olasewere provided a double-double of 15 points and 10 rebounds as the Blackbirds (20-13) collected their straight NEC Tournament championship. Kenny Onyechi helped out with 11 points and seven rebounds.
The Mountaineers (18-14) got 21 points from Sam Prescott but still saw their nine-game winning streak broken.
Shivaughn Wiggins (11 points), Rashad Whack and Julian Norfleet (10 apiece) also reached double figures for Mount St. Mary's.
Video of Victoria’s Secret models trying to 'twerk' hits Instagram
Wisconsin business offering 'therapeutic cuddling' forced to close