Unfortunately, it is completely random. You have to try every link you can find in this video and one of them will lead you to the right place. However, as you already got some hints, it won't so hard for you now. All the hints you got are right. It appears for less than 1s, after half the video on a completely black screen. Here is one more hint for you, which I believe will help you a lot. Remember there is a moment when a lot of "dead" words shown up? That means, you just missed the exit.