here's the text from the game log.
3-15-SJE 20 (13:41) 16-Sean Lawlor pass complete to 15-Robert Hernandez to SJE 31 for 11 yards. 15-Robert Hernandez FUMBLES (43-Angel Reinoso) recovered by SJE-32-Chad Gasser to SJE 35 for 3 yards. Tackle by 42-William Wright. Pressure by 99-Lawrence Miller. SJE 15-Robert Hernandez was injured on the play.
Looks like the ball advanced a yard or two on its own and then player who picked it up advanced it three more yards for a total of 15 yards, which is what was needed for the first down.