i think it will be the captive population that saves them
That approach has been tried back in 1995. When private collectors figured they could captive reproduce animals on the same level as Zoos. It did not come close to working. Even with captive breeding, wild populations for sustainable populations has been proven as the only way to go. As even with breeding Panther chameleons in captivity, breeders have only been able to breed them in captivity for 5 or 6 generations then normal reproduction seems to stop. Parsons have been proven as nowhere near as compatible for captive breeding as Panther chameleons and if you think captive breeding is going to save them you are kidding yourself big time.