Lyman;
Use of the word "Level" is misleading, for it implies that she lingered at level.
Passing through "level" at apogee does not imply "lingering".
To remain level whilst moving implies lift, she had none, she was above the Lift ceiling. Her controls had no purchase, her engines were above propulsive ceiling, and so on.
A normal acceleration of 0.75 g means that lift is about 75% of weight. Lift ceiling and propulsive ceiling are not directly relevant and do not affect controllability.
What is the lag between actuation of ND elevators and screw jack actuation?
I don't know that, but perhaps you can get an idea by looking for changes of THS position before 02:10:50 in response to NU and ND elevator movements?