Of course changes have to be made, but I think it's critical to still assume Zurich was and is still at fault. I too have read articles on it written by the ARA's, but as is most media articles (especially those by ARA's), they're written from one side.
Some background information for you;
The first two calves passed from EEHV - you can't blame them for that. They also lost two newborn calves within quick succession back in 2020, of whom were accidentally killed at birth. The easy fix would have been to then isolate the mother/s at birth for their next calves, and Zurich seemingly did so as the next two calves born survived birth initially. One of the calves was born with a medical condition and was essentially inevitably going to pass. And the most recent, Zali, passed following a leg injury (which is just a tragic accident). I'm sure they would have deduced how that occurred, and have made changes to ensure it doesn't occur again.
It would be one thing if Zurich had elephants continuously pass from the same cause - but it seems like they have just had poor luck.