Quiet Down Warden!

You can add blocks to the 'dampens vibrations' tag, and they'll have the same properties of wool. ...Otherwise, to the best of my knowledge, there isn't a good way to block vibrations. If you really need a weird workaround, you could try resetting the warden's attack target. (By spawning an invisible/unkillable entity nearby, setting the warden's attack target to it, and then immedieately despawning the invisible entity.) That'll deaggro them from the player, but won't actually silence the noises.