He dosent have inner destruction, that is pretty much confirmed.
But its not like people who use sharp weapons would be able to apply that into combat anyway, we dont know how the last level of adv armament haki looks for swordmen yet...I still do think that it was what we saw him doing in allabasta, being able to choose what he can and cannot cut at will.
Its also a possibility that its either the kind of Haki that makes Roger and WB's blades unnable to touch, or that kind of thing might even be some 4th level of haki that is yet to be explained to us.