I don't know if it is the same one, since there appears to be several Vulcan misfires on the web, but it apparently happened when loading it.
I am always sorry to hear of anyone being injured by a firearm, but this incident does not appear to be the fault of the shooter.
There was an amazingly long interval before someone started yelling for a cease fire. After that, a range officer (I think) starts yelling for "a shitton of towels". That's not the sort of response that gives me the warm fuzzies.