A Q on horizontal turns

During a cruise, just pressing on one of the rudders should make an
aircraft turn horizontally in that direction, when no ailerons are
used. Reducing power in the opposite engine should logically accelerate
such a turn.

Makes me wonder why then was it is that, in the crash at the end of
2001 just outside of NY, the A300's rear bulkhead came loose when the
pilot used the rudder to correct a yaw induced by probably a wake
vortex ?

Ramapriya