Had to walk.

Hold on tight to both handrails, you hot, virile, lithe, muscular, hunky man, you!!

He better be happy he had a klettersteig to help him up.

Escalators are designed and rigorously maintained to run for thousands of hours without failure. This would be especially true at a high profile and well funded building like the UN. For it to miraculously fail just as that stronzo (an apt Italian curse) got on would either be a woefully weak act of God or more likely, somebody at the top of the escalator smashed the emergency stop button. I'd like to buy that guy or gal a good bottle of wine.

That's now in my active vocabulary!

That is all

My bet - someone hit a switch

I watched the video and the escalator to the right was moving along rather nicely.
Why didn't they just step to the right(pun intended) and go up that one? It seemed to go to the same place.

could have been a life-or-death decision on his part. He made the wrong choice, IMO.