I guess this is where we partially agree. I'm all for not using leashes with wild mammals (if a zoo puts a rabbit on a leash, or other domestic, I'm all for it), however there are plenty of ways to use mammals as ambassadors when they aren't leashed. Some zoos have built exercise yards for these sorts of presentations, where visitors can get an up-close look at animal ambassadors while they are displaying natural behaviors. Furthermore, even if there aren't a designated exercise yard, zoos can use temporary pens/gates to contain an animal while it isn't on a leash. Alternatively (and I'd argue even better), is to train animal ambassadors such that they don't need a leash. Especially if you always have two staff members nearby, and choose appropriate individuals of appropriate species, I don't see any reason that using mammal ambassadors inherently need to be leashed. Truthfully, it's been very rare that I've seen zoos with exotic mammal ambassadors leashed, and I've seen quite a number of ambassador mammals.I have previously stated on another thread that I am not a big fan of non-domestic mammals being used for educational shows especially by members of the AZA. I hate to sound like an animal rights activist but I think there are other ways to educate the public other than putting a cheetah on a leash. Sure the event may be memorable to the audience due to the novelty of seeing an exotic animal on a leash, but I am not sure if the information told to the guests would stick on them. I'd also argue that having a cheetah or a clouded leopard on a leash undermines that these animals are wild animals and could cause harm.
To add on, when you say no non-domesticated mammals, where do you draw this line? I can understand being against using big cats, or even stuff like fennec foxes, on this regard, but what about a lot of small mammals? For instance, many zoos use hedgehogs or tenrecs as ambassador animals, oftentimes displayed on a presenter's glove, and I don't see any reason why this should be considered unacceptable, if it's acceptable to use a rabbit, ferret, or chinchilla. Taking it to the next level, what about native non-releasable wildlife? Ambassador animal departments have often been a great home for orphaned or otherwise non-releasable striped skunks, virginia oppossums, groundhogs, or other similar species. It'd be a real shame, in my opinion, if these animals stop getting these great permanent homes just because they are mammals. Another species, that in my opinion makes one of the best animal ambassadors, but is a mammal, is armadillos. Despite being a mammal, these are very misunderstood animals, and usually aren't displayed using a leash. So I guess that's where we differ. I think that the leash is the problem, not the animal inherently is the problem, as there are many great mammal ambassadors that don't require leashes and are great for educational opportunities (especially looking beyond "shows"- visits to schools, camps, etc. is way more of what an animal ambassador does at most zoos).