When a speaker is rated for a certain wattage, it's for all speakers and the crossover, not any individual component. And, even then, it may well be for a brief burst as opposed to continious.
As another said, woofers are the mosrt rugerd and can withstamd much more power than mids or tweets. It may only take a handfull of watts to blow out a tweeter in a 500 watt system if that's the only thing being played, and being played loud.
Not being there, my $$ is that a very compressed piece of music was being played very loud and, if there was a LOT of activity in the midrange (which would add punch), then it's possible that, like a magnifying glass can focus sunlight, a heckuva lot of pure midrange power wound up being directed right at that poor midrange and perhaps the tweeters as well.
It may bot beclippping in the traditional sense, but most likely more than enough concentrated power for the drivers to shuck their mortal coils (pun intended).