From the post by FDMII #1989
From the Hudson A320 view of the Port THS pivots, the attachment point to the fuselage of the twin supports is pictured in the lower photo of the Metrojet framed by the inverted V of the cables - showing a broken support.
If this was the initial failure point, then downward pressure on the THS would rotate the THS about the remaining Starboard pivot and the jackscrew altering the relative angle of attack more of the Starboard THS creating a twisting effect on the rear fuselage.