No, with availability factored in as well, I doubt Melbourne would import anything more than a pair of Bonobo - and even that’s something we can all agree is unlikely. They’d be a nice link to the Pygmy hippopotamus, not only are they both Central African forest species, but the Bonobo is also known as the Pygmy chimpanzee.
The Mandrill would be better suited to the space the baboon exhibit would offer (planting would still be required) as Mandrill thrive in large troops. Even if Melbourne could only import 1.2 Mandrill, a sizeable troop could be built up over the decade that followed; with Adelaide potentially importing and collaborating with Melbourne to exchange males after several daughters have been born in the two troops.