@Jonathan Harry honestly, I think I need to say this to you that not all animals in Indonesian facilities are acquired from another zoos that have/had them. If some other zoos have dart frogs, it doesn't mean they came from Jakarta Aquarium or Jagat Satwa. I mean, wouldn't any facility though of getting this animals from private suppliers or import them? I have to genueinely admit that comments like these can be very misleading if you barely given any credible sources, let alone further details.
Honestly, where do you even get this and the alligator snapping turtles at Suraloka "informations" from?
These pair were acquired in around 2022, long after the oryx in Ragunan were gone.
Though there are no confirmation so far, these are likely new oryx imported from farms in say UAE, where the management have a close relationship with the local private collectors. Again, this are assumptions and not a fact, but I still bring some plausible explanation that backed it up.