Way, way too early to speculate, but I'm gonna anyway. So far it seems that the plane for sure was following standard procedures, plus if it was on final, that much less probability of them having done something wrong. Maybe NOT done something in time, but we don't know yet. News I heard said that the Blackhawk was on a transport flight, but I wonder if that was accurate. I'm curious if maybe it was on a training flight, like maybe IFR training for the pilot or something, and things went wrong and the instructor pilot didn't catch it in time.
I don't want to place blame with so little information, but it seems to be pointing to a problem with the helo.