At 0:22 the dark void might be there but until you collect all 79 gold coins, the sword & the surrounding area won't manifest. It's interesting though that the dark void is there at all prior to collecting all the gold coins. It does make me think that the dark void right next to the lair of colossus 11 (Celosia) might also be accessible once a certain something is accomplished. If nothing else the rectangle shape of the dark void in this location is a curiosity.
In the other video you said it won't load the room without all coins. I got all the coins and the sword, I just want to see the top of the room when it's loaded in.