No, I do not make my living selling zoanthids, but I have worked at a lab that did testing for toxic substances on blood, tissue, etc. Palytoxin is being used in cancer research right now as well.. and I happen to know a bit about marine toxins in general through my training.
I am NOT calling him a liar, I am just stating that sometimes what we think caused the death of something actually turns out to be quite different than what our "intuition" tells us. I know its a loved one, but be careful how quickly you assign causation. Examine the exact toxin/cause of death and I will believe it.
Now, can a dog die of Palytoxin? Absolutely. Do I think this dog died of Palytoxin? No.
Why? I would ask these questions. How long was the show? Did the dog spend many hours at this aquarium show? Did he possibly ingest a crab, small fish, or chunk of algae?
Reason I ask is because TTX poisoning is SO much more common in reef animals. Palytoxins are ultra rare, with most zoanthids in the pet trade (even 99% of the live caught) containing small amounts of this poison and no other organism carry Palytoxin. Actually its a very very particular type of Palythoa that contains the toxin in measurable quantities.
I suggest the dog might have eaten a small pufferfish, a seastar, boxfish, goby, or some other animal that stores TTX.
Guys, one of the first things they teach in marine biology is how common marine toxins are, and also how potent. But they usually don't even mention Palytoxin, because of how rare it is.
SO MANY animals at a reef show, if ingested (especially!) will cause toxicity in animals, humans, dogs, cats, whatever.
The skin on your hands usually will protect you from these toxins, just like snake venom. Just don't get it in cuts, scrapes, and mucus membranes.
Dogs (who eat practically anything with caloric value) will ingest things (like small crabs and stars) that fall on the ground. That is where TTX could have killed him.
I bet very very few people on Reefcentral understand TTX, how common is it in the marine ecosystem, and how much more likely TTX would be a culprit in the death of a dog at a Marine show.
Sorry to **** anyone off, it was not my intention.