The spoon-fed data the NTSB has released is a bit confusing and I would expect that we don't know the exact sequence of flight dynamics.
I think the pitch up prior to the stick pusher could have happened even without the PF over-riding it. If the crew called for max/firewall power at the stick shaker when they became aware of the low speed situation, the plane would pitch up quite quickly with no manual inputs. This is because the aircraft would have had significant nose up trim to maintain the slow speed and now the autopilot is kicked off. With the combination of increased prop wash over the elevator and the aircraft literally "powering" it's way to the nose-up attitude, I can easily see the aircraft attaining a 31 degree nose-up attitude prior to stick-pusher activation....and all this without any input from the pilot.