Maybe, but I don't think it matters. In fact I think the whole cancelling of reverse and attempting to go is a complete red herring.
- The captain elects to make a landing which was so unstable as to be lethal.
- He adds thrust just before touchdown (possible in response the the GPWS).
- He floats horribly (due to the automatic moving of the flaps back to 40), and still doesn't go around.
- Having landed, he fails to stand on the brakes, and fails to give it max reverse.
- They reach the end of the runway, turning slightly left, at around 80-90 knots.
In my mind, the accident is secured at this point.
As they arrive at the end of the runway, there is a cliff edge. Visually you are left with only one option, which is to try and fly again. In fact, it may have looked like they were going to fly anyway, so you might as well try doing that with thrust on.
The reversers were only cancelled at the runway end just before the cliff, as a last ditch option*. The accident had already happened, so who did it doesn't really matter. All they did was change the "crash configuration".
* see page 169/175