They're wonderful chameleons but far more sensitive than veileds and panthers. They decline quickly if not properly cared for. Sometimes they decline even if they are properly cared for. Most available are wild caught and acclimating them can be tricky.
We have four very healthy melleri and adore them. We've taken in a few that were ill due to improper care and it is heart-breaking to watch them fail no matter what you do.
Ours are free-ranged, we have found that to work best for them. We have a automatic misting system (AquaZamp) as they need plenty of water, and we hand feed them to be sure everyone gets their share - and only their share!
The melleri discovery has a lot of good info. And I'm happy to do my best to answer any questions you have.