Focus less on actual armor and more on keeping the enemy at a distance. Ranged weaponry is your friend. Speaking of friends, heavily armored trained warbeasts (rhinos, elephants, etc) can be used to directly engage while the Lokk stay back. Light calvary (lightly armored, fast moving, armed with bows, slings or javalins), will allow the Lokk to strike and not remain in place to be smacked with blunt force. Of course, as the Emperor has declared that the solution is to wear armor, it will be the job of his advisors to not have their heads removed while attempting to let the Emperor know that his solution is not practical.