Spotanim is the oldschool naming of the gfx configurations. In older revisions, these were stored in a single archive within the config cache index archive 13 within cache index 2.
In 718, these would be within index 21. Those really shouldnt deal with the model shrinking. Sequence definitions are stored in index 20, and you can get the data from OSRS index 2 archive 12. Not sure how you are packing but I would think you dont have the sequences properly packed.