Brandon Wood added 15 points for the Crusaders (16-6, 8-2 Horizon), who rallied after trailing by nine early in the second half.
Kenney scored on a layup a minute into overtime then assisted on Broekhoff's 3-poineter 32 seconds later to give Valparaiso a five-point lead. Butler pulled to within 74-72 with 2:10 left but couldn't get any closer.
The Bulldogs led 31-26 at halftime and took their biggest lead, 40-31, on Khyle Marshall's free throw with 15:50 left in the second half. The game went into overtime after Howard converted a three-point play to tie it at 67 with 30 seconds remaining in regulation.