Try and use this speech folder then. Its the extracted Stormboyz speech from the game which must work. It only has the bare minimum speech events like Unit_Complete, Selection, Move, Attack, and Jump.
Ok whenever I extract a speech file it corrupts the whole thing for example I just done the stormboyz and my leader beeped but as soon as I deleted it from the W40K and my mod folder their diologue worked again.