I have seen comments that the AA CJ was diverted to a different runway. In the video I've seen, there was an aircraft taking off and banking to the left when the incident happened. I am wondering if the helo crew figured the AA flight was landing on the main runway and when asked, couldn't see them among the ground light clutter. Still, no reason I can see for that helo to be anywhere near that spot and ATC asking them if they had a visual on the CRJ indicates, to me, that ATC didn't have a picture was to what was going on.