Thats true I guess, he could just take leadership. I guess I think of that feat as being "The Taboo Feat" because almost nobody allows it, and even Paizo and WOTC before them said that this feat could only ever be taken with DM approval as a warning of its power. Would you allow this in your game though? 1 feat for an animal companion and a bunch of followers seems a bit unbalanced. Although I guess it wouldn't actually be an animal companion. Come to think of it I'm not quite sure how this would even work rules wise, taking an animal instead of another character as your cohort. I mean I know there are rules for players taking non standard races with a level offset in PF. Hmmm.
I wonder if an animal only version of leadership that requires 3 feats would be fair.... You get 1 animal (possibly a magical beast) that is decent strength, and then you get a lot of lesser animals that are more like useful tools (such as combing a forest looking for a trail).