looks to me like you got exactly what you ordered.
It's not rare, more common then you think. They often call this type "grape coral" as it's family is with the hammer, froggy, and torch.
I see A LOT of truths from experienced people here, BUT mixed with almost as much untruths, even from the 17 yr experience(no offense!). This thread is a perfect example how misinformation gets passed around region to region to the point it's accepted as common knowledge. Generalizations, and ol school words
Euphyllia divisia aka frogspawn is not another word or ol school word for
octopus coral aka Euphyllia yaeyamensis. Two distinct species. HOWEVER! Both branch in growth form. I have a branching yaeyamensis at the museum where I work. Definitely way more uncommon.
you can see the difference pretty clearly the regular has 1-5 nodes on any given tenticle, while the octo will have 8+ on any given one, and looks a lot like a cluster of grapes, or more appropriatly octopus tenticles.