This short video was sent by a co-worker who works the ramp and teaches safety. This picture (funny he took this picture as well) is not the B747 in question. I used it for clarity.
When you watch the short clip it shows the lead in the foreground trying to get confirmation from the flight deck the brakes are set. Many things seem a bit odd. It occurs at JFK and a tow was required onto the gate. Some airports still do this but it's rare. Another thing is all the engines are running. And thirdly, a headset was not used to converse with the flight deck. It's one thing we do on the "heavy fleet."
It goes to show how dangerous a ramp can be. This tow truck weighs 6o tons. I've seen it where the marshaller was directing me, while walking backwards, he fell over another tow bar. I've also seen a small vehicle come behind the marshaller and the marshaller almost walked backwards into the vehicle.
As one pilot told me, the park brake is your friend. If you have an issue, set the brake and deal with it. When I come to the gate I have a routine I do. For one thing I say everything out loud.
After I stop, I set the parking brake but wait until it actually shows on the screen and the pressure gauge by saying, "brakes set." I immediately turn #2 engine off by saying, "two is off," "seat belt sign off." Pause...wait for the electrical transfer on the engine and say "number one is off," "beacon is off" and then watch the "rampie" give me the sign the chocks are in and I return with a "brakes set" signal with two closed fists.