Well, in a worst-case scenario that leaves the Georgia Aquarium without any whale, tiger, or great hammerhead sharks in the future, they will still have giant oceanic manta rays, the only holder in North America. In fact, that was the primary draw for me when I first visited, not the whale sharks (although I love both). I’ve no doubt that they’ll figure something out if they have to.
At the risk of sounding cynical, whale sharks end up in bycatch all the time and I wouldn't be shocked to see them "rescue" one of these individuals down the line