Latest report I read speculated the victims might have put a board across the moat or something that allowed easier escape.
If that's the true, the zoo is more at fault for not monitoring its dipshirt patrons more so than any negligence for the design of its enclosures.
And OoP, c'mon. At EVERY zoo I've ever been to, I wouldn't take THAT much to get into an enclosure if you were bound and determined. Don't try to sell that unsafe enclosure argument, these victims were baiting a dangerous animal.
And as far as that tiger "mauling" someone earlier, that tiger gauged a zookeeper's arm in its cage when it was being fed. Everything I read said that it's normal behavior for a tiger to do that under certain circumstances (the inference I read into it was that the zookeeper might have not been on the ball). So by that logic, let's go around blasting away all the tigers in every zoo.
By the way, I'm not trying to say it's tragic the tiger died, if it got loose, you have to kill it.