The first CCTV video shows a vertical descent due to camera angle, the dashcam footage shows a steep descent but not vertical.
Its difficult to see if the aircraft is right side up or inverted.
One thing I want to emphasize here, it is entirely possible to regain control after an upset and still be in an unrecoverable situation due to lack of altitude.
As in the airplane is under positive pilot control and still crashes.
Simulator upset training will show you how little time you have before the situation becomes unrecoverable either because the airplane is so far out of the envelope that it will come apart during the recovery or insufficient altitude.
This is obviously a PC simulation freeze frame but it’s the best picture to illustrate a possible scenario. Airplane ends up inverted and nose down. “Pulling through” as if flying a part loop will over stress the airframe and take a tremendous amount of altitude. Rolling upright and pulling out of the dive will overstress the airplane and run out of altitude.
The question that remains is what got them there?