Just got a response from the admins. Interesting:
The sim looks at a variety of factors for whether a ground ball can be turned into a DP:
how hard was the ball hit
how fast are the runners on base
how fast is the hitter (including whether from left or right side of the plate)
fielder's range (for the throw)
fielder's range (for the pivot)
game situation (score, inning, outs)
All things equal, RH should hit into more DP than LH.