Curious...ady... perhaps the turret should just be a smuldering stump because...well... my guess is that it didn't survive the onslought of the attack... ;-)
And also, in that same shot... there's an AT-AT that shoots a soldier and then it shoots the shield generator... do you think it would HONESTLY take the time to do that?
Maybe you should have another AT-AT... or an AT-ST shoot the soldier...