This is correct.
What happened was there is a tab on the cable, and that didn't go all the way through the casing. I made this mistake about 3 times. It's not too short, just move the screen a little away from the casing, and pull the cable all the way through without ripping it.
If you look at the Logic Board, the top kind of looks like steps. Find the tallest point, the go left and down one step. The piece goes at the top of this. The thinner part should face towards the back of the phone. It is to protect the LCD cable.