From what I remember, that was a problem which had been considered, and I believe early trials showed a distinct possibility of this. However, the 'stills', from what I recall, show the top wing 'lifting' at the leading edge as it's jettisoned, with the next shot showing the wing quite high above the mid fuselage section, and the third shot showing it behind the aircraft, at the start of what could be described as a wing tip stall.
I'll dig through the stuff I still haven't un-packed after moving house fourteen years ago(!), and if it's not there, then it'll probably be at my ex-wife's house, in the loft somewhere!