I'd really like to see that other video because apparently both officers fired their gun. It seems quite plausible to me that both officers were reacting to something the public video doesn't show. I'm trying to think of other reasons and I've come up with a) one fired and the other reacted with a kind of reflex, would think they're trained against that though, or b) both officers had really poor judgement at the same time, or c) both officers enjoy shooting people. The video doesn't look good, but I'm on the fence.
FWIW in the Jessica H case, the explanation for both officers firing in the final analysis was a). Not wishing to detract from this thread though by further discussing JH.