Check Memory address
As you can see this is the main counter for each animation frame. It is adding 1 to each frame, advancing the animations. Hence, making this value 2 doubles anim speed.
Surely there is a way from here or nearby to make it count 4x slower. I am not sure what calls this function, or how it all ties in. I only know that the key to animation is here, and this appears to be the main thing.