From the perspective of an outside observer, nothing ever reaches past the event horizon- it just asymptotically approaches it. The same goes for the whole mass of the black of hole- from an outside perspective, it's smeared across the surface.
There isn't an object that messes with the warping of spacetime- the black hole IS the warp in spacetime. If changes in spacetime couldn't propagate away from the black hole, it wouldn't exist.
I understand that from an external POV things that fall into a black hole never seem to reach the event horizon, but there must be material that is inside the event horizon. When the original star collapsed and the black hole formed, there was material inside the volume enveloped by the new event horizon. Also as more matter accumulates in the accretion disc of the black hole the event horizon will expand. With these enormous super-massive black holes, with event horizons the size of earth's orbit, there must be something inside the event horizon.
Or is that wrong, and everything just smears out even more finely as the event horizon grows?
There isn't an object that messes with the warping of spacetime- the black hole IS the warp in spacetime. If changes in spacetime couldn't propagate away from the black hole, it wouldn't exist.