Most likely many of the wounded were hit by bullet fragments, rather than a direct hit. I would imagine a few more were injured during the panic to get out of there. With a packed crowd like that, and several minutes of shooting, I think the number of casualties is realistic.

But I agree, a lot of this just doesn't compute. If anything, this reminds me of the Texas clock tower shooting, where it turned out Charles Whitman had a brain tumor. Whitman went up the clock tower with a bunch of weapons and ammo, and no plan to survive the shootings.

Onward and upward,
airforce