Don't confuse the issue by putting both in the same theory.
They found the vertical tail in the water behind where the aircraft had flown.
An aircraft cannot be flown with no yaw control. They roll over into a spin and parts start coming off.
The verticle tail is of composit on that aircraft, and it cannot take the stress that was put on it by the pilot.
It broke off.
I have to wonder what we would have been told happened if the Shoe Bomber had been successful.
His attempt is still not listed often among TERRORIST ATTACKS since 9-11. Just becuase he was unsuccessful does not mean the attack didn't happen. He was stopped IN THE ACT.