Possible that relief well causes cave-in?

Forgive me if this is an ignorant question but could it be possible that if this new well they are drilling to intercept the present one's path through the sea floor (done in 2 or 3 nonths), eventually cause a massive cave in, in between the two wells? Perhaps an earthquake, that we never hear about in the Gulf because it is so far beneath the earth's surface, triggers this cave in. Im thinking if this happens, that massive amount of earth would fall in to the present path of the "river" of oil, then force this oil upwards through to the surface and create and even worse case scenario. Just a thought.