There is a big clue in that video as to how it was done.
When the drum crashed to the ground there was a rope hanging out of the drum.
Arthur was very embarrassed when he saw that, he forgot to shove it down his underpants once he was out.
There are no safety guarantees in that business. With all the time I spent with magicians and illusionists there is an element of risk to life or the effect is not complete. There are some risks I may have taken when I was younger and stupid. Like the time I put my head upside down in a full size guillotine and watched the blade come down. I knew it was safe but I wouldn't do it again, scared the shite out of me.