The second video is completely different. The player in white is jumping in like in the first video, but he is leading with his elbow into the head of the opponent. In the first video, the impact area was not the player's head but his body.
The other difference is in the first video, the defender clearly sees the other player coming at him, which is why he releases the ball, in the second video the player in red is watching the ball and never sees the player in white coming. You can tell in the second video that the white player is never going to play the ball, whereas in the first video you can't make that statement because the defender released the ball a second before contact was made.
The second video is a classic case of serious foul play and should be a red card.
