That’s disappointing, hopefully the Taronga pair and Kamina and Obi/Felix will be able to sustain the population enough until new imports come in (if that ever happens).
Assuming no imports are on the horizon, Taronga should definitely focus on breeding Fergus and Kambiri again. The priority is to get female calves, but three more calves (a male and two female) could theoretically supply the other three zoos with a mate for their Pygmy hippopotamus. The priority should be Felix, given he’s the oldest.
What I’d rather see though is Melbourne or Darling Downs Zoo loan their hippo to the other for breeding while we wait. It could be years before Taronga breed again (and a further three years minimum before that calf is mature) - we’re potentially wasting valuable breeding years here.