According to the article that you included a link to, only two more penguins have arrived, for a total of ten.Another ten Humboldt penguins have arrived for the new Galapagos complex.
Houston Zoo welcomes 10 Humboldt penguins for new Galápagos Islands exhibit
I was surprised to see that the Galápagos reef tank will have bonnethead sharks and blacktip reef sharks, neither of which are common in the archipelago. I am fairly certain that whitetip reef sharks are easily acquired, so that species would have been a better choice in my opinion. Scalloped hammerheads or blacktip sharks (not blacktip reef) or both might have been better choices, too, but I am not sure if they could be sourced appropriately.
I'm surprised that they don't have any Galapagos Sharks planned for it, considering that a few aquariums in the US have them, and while not excusive to the islands they are named after them. Scalloped Hammerheads and Blacktip Sharks are not common from what I know, but it is strange that they don't have Whitetip Reef Sharks there a dime a dozen and fit better thematically, I can understand the blacktip reef sharks serving as a stand in for blacktip sharks, but no one would confuse a scalloped hammerhead with a bonnethead.