I think he's alone. If you watch closely when he approaches the gate, I can see the gun holster swing out from his waist. He also has his jacket unzipped and places his hand at his waist a couple of time, probably because the gun keeps swinging out. I think it's the same dude. It's at the 10-11 second part. Enlarge your video:
i kinda see something black swing in front of his waist for a split second at the 11 second mark, but hard to tell what it is. if anything. :/
but what i don't understand is what he's even doing over the fence. it's not like he's taking or handing the backpack to someone else because he holds onto the same bag the entire time. maybe hanging it over the fence for someone else to put something in it? weird.