Whether a bug, whether I'm an addict (Little Nightmares)

Guys, I need help. Passed the second addition to the game, got to the point where gnome free pull trolley and need to get her upstairs. Here I got stuck, as it forces the two of us was not enough to lift it up on the hill, began to look for another one. Went on YouTube. And here is how you need to climb up the crates and climb into the ventilation hole. Here is the screenshot, need to get on a small ledge near the drawers.
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Tried to make screenshots as I could, like seen.
Climb to the ledge, and then stupidly up. But the whole problem is that THIS LEDGE is NOT STUPID! It's like a different texture.
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Tried to jump a very long time, does not come out stupid because of the ledge there. To jump simply. Sitting in confusion XS what to do. Some tin, comrades. I understand that the problem is very strange, but also how to try to ask nothing more I can do.