"I've lost control"
Probably referring to roll rather than pitch?
Sticking my neck out, but this is why I think that when he said that he was almost entirely correct.
1. With the wing completely stalled, the ailerons would have been useless - no roll control, but maybe some adverse yaw.
2. At that sort of AoA the rudder power would be severely limited because (a) it was working at something like 70 deg effective sweep and (b) it was probably sat in the low energy wake of the stalled wing.
3. The elevators and THS were working.
4. When you roll an aircraft around the fuselage axis at high AoA you get an increase in sideslip and a reduction in AoA just from the geometry.
5. Changes in AoA produce changes in pitching moment and that in turn changes the pitch attitude. So there is a pitch/roll coupling.
6. At high AoA, as I have said before, the Dutch roll changes to a lightly damped or constant amplitude roll/sideslip oscillation. This will be accompanied by a corresponding pitch oscillation. [Check out the traces - the roll and pitch oscillations have similar frequency and much the same relative phasing throughout once the aircraft is stalled]
7. He would not be able to control the roll oscillation - with zero aileron effectiveness no amount of thrashing of the sidestick is going to make any difference.
8. He would not be able to suppress the pitch oscillation by using elevators because the motion would have been perpetually regenerated by the roll motion.
9. No wonder he thought he had lost control!
10. The only vestige of control left to him would have been a steady application of down elevator to reduce AoA, after which the other problems would disappear. Tragically this was the one option he did not try.