As far as I know, the animations are only available as part of the Legendary Patreon supporter tier. So you would need to "subscribe" to that tier at least once to get those rewards.
You don't have to subscribe to the Patreon, but if you already bought the game it seems you unfortunately do still need to pay the whole $15 to get the Art & Animation Bundle. That's what I did, and I can confirm it now lets me download the animation pack from itch.
