I changed an animation name to a name that is not in war3 and it cant see that animation in the game, it can see the animation with the name i gived it Magos ME but in war3 not, so u will have to use the recognized strings like: Attack, Spell, Swim.
U can use Art Tools or NeoDex to change animations names.
But the names are not a problem because i added almost 20 attack animations to a Sea Giant and it works fine.
I placed them on attack: Attack - 1, Attack - 2, Attack - 8 ... Attack - 17.
I think u may have many animations.