Exact same thing happened. Exact! Hasn't happened again, and I do suspect that in the 'stress' of the situation I might not have had my foot on the brake hard enough. Just resting on the pedal isn't enough to disengage the lock-out.I abandoned my shift to neutral technique after an unfortunate incident with the car. There I was in neutral at a light, in my brand new expensive racy car still with dealer plates. Green light, hit the paddle for first, and ... nothing. Hit again - nothing. Again - nothing. Shout at car, shift - nothing. Shake fists in fury at invisible gods of automotive reliability, shift - nothing.
Finally, after turning the car off and on a few times, I was able to shift and slink away, tail between my legs. I was not amused. The dealer suggested that I might not have had my foot on the brake pedal fully, and it might be true, but we shall see.