... you can look from above at Greencom and see what happened
Well, the VirtualEye replay doesn't exactly match the on-boat video, so I'm a little suspect of the sensor data. For instance, VirtualEye shows Aleph turning up into GreenComm and hitting her starboard hull broadside rather then bearing away and catching the inside of her port hull at the rudder post.
What VE does indicate, however, is that GreenComm tried to tack from port to starboard, but went into irons before completing her tack. She then drifted backwards onto port tack again in front of Aleph. GreenComm was moving forward just before contact so she was either on port tack (if she achieved a close-hauled courese), or still tacking (if she was moving forward but above close-hauled). In either case, GreenComm was the keep-clear boat.
At least, that's what the ROW would be if the America's Cup Series was run under the Racing Rules of Sailing - which I don't believe is so.
Regards,
Eric