From 52.128 to 52.688 there are 14 black frames: after them, the full scene returns: in 40 milliseconds it switches from this Attachment 335474
to this Attachment 335475
the change occurs suddenly, not gradually.
There the video could have been stopped and edited in order to add the second scene, which could have been staged while the camera was off.
Also the position of the body doesn't look consistent with the way she fell: too far from the wall (she didn't jump, she just fell) and the body should have rotated clockwise by 90 degrees during the fall for no reason. Attachment 335476 Attachment 335477
I vote fake, but i could be wrong: thanks for sharing anyway.