I tried getting two elefants into a battle with the panther type, went guns blazing (sent all the panthers elsewhere, with weapons safetied) had both of them blasting vehicles until they hit 30.....went to the leadership screen and it showed zero of five.....and its not the only one that doesn't count (even in a 1 vs 4 battle, took 3-4 elefants, kept track of kills....nothing)

About teh otehr achievement of the elefant?