Griffin had 16, Engesser, who made 3 of 5 from beyond the arc, had 13 and Brett Olson chipped in 11.
Denver held a 31-23 lead at the break and pushed that to 43-23 with 15:56 left in the game. Brandon Pye nailed a 3-point jumper to close to 50-41 with 7:36 left, but the Islanders could get no closer.
The Pioneers, who shot 40 percent from long range, made 25 of 45 field goal attempts (55.6 percent) while limiting the Islanders to 15-of-43 shooting (34.9 percent).
Denver (4-3) picked up 19 points off of 14 A&M-Corpus Christi turnovers.