At about 8s into the video the screen goes dark and then light again. That looks to me like the contrast trimmer is doing it's job, but it's done so fast it's hard to see.
Comparing to the examples it also seems the display is upside down in the OP's photo's. The most common mistake would be getting the position of Pin1 wrong and working from that.
It's all difficult to follow though. A drawing showing the row of LCD connections, with which pin each has been taken to, would be useful for an independent verification of whether the wiring is correct.
We all sit and stare at problems where we're convinced we've wired everything correct or coded it correctly, until suddenly we notice the problem or someone else looks and sees it straight away.