While I'm generally against the zoo losing more species, it's probably the right thing to do. As I've perviously said, the zoo doesn't currently have adequate facilities to humanely house both Chimpanzees and Orangutans. Building a new enclosure or renovating an existing one will take years. Rehoming the Chimps and moving the Orangs to the Chimp area will allow them to do work on the triple grottos as an expanded area for the Orangutans and potentially Gibbons.
Another species that needs to be rehomed are the poor Francois Langurs, who've been cooped up in those awful archaic cages for years. None of the zoos existing exhibits are ideal for housing them and it's unlikely to be able to build in a new one in a timely manner.