How did the 'attacker' just happen to have a wardialer and know to use it that night? Why couldn't the NOC just shut off that one guy's service? Why can't I find any reference to this in the news? (they always love a good cracker story). How was a company that big operating in such an ad-hoc manner?
Also, as already pointed out, this does not seem to be a big company at all. In a world where even a idiot can start a company, you will eventually end up with companies run by idiots.
Given that market forces determine which companies survive, if we eventually end up with companies run by idiots, it tells something about the rest of us too.
Also, taking big risks can be very profitable... for a while. It sounds like they were running seat of the pants, and it caught up with them.
This is some off-brand calling card company, not Verizon.
Why wasn't it in the news? Well, because nobody ever told them. It's not like you'd issue a press release.
And why were they running such a cheap operation? Because they were stupid and greedy.
(Not saying the story is 100% true, but it's certainly plausible)