"It's in the name"
No it's not really. It's name is Tilly and it's an Orcinus orca. I could call my hamster a killer hamster but wouldn't make it so. Even if it did kill someone it wouldn't make the genus killers.
If the whales were known as killers of humans before they captured it, locked it in a small tank and forced it to perform tricks then the blame couldn't be really placed on the animal now could it?