That's what I've been saying. He wasn't lurking around some corner or even being constantly rebuffed as he tried to talk to them or put a hand around one's waist or something. He was right there. He was laughing and joking with the other guys.
Just because he wasn't skipping down the street arm-in-arm with the girls doesn't necessarily mean anything. They were drunk and goofing around in their own little world while they waited for their food. I don't think we know what happened after everyone leaves the video (I bet the police do), but I didn't get rage in his waving of the arms... I thought it was more of a "what the heck, there go my drunk friends" type of thing.
Surely he (and others in that video) need to be interviewed - but I feel like the people that seem most focused on the video are doing so because it's the only video they have to focus on. If we had access to the CCTV from the bar and elsewhere, I bet we'd have a dozen other suspicious guys!