This is the point in the video where Oswald goes straight down like a freight elevator at the TSBD. It's like he is sucked down into the vortex. All he could do is fall, and when you fall, you accelerate. But, with Oswald it was a woosh straight down. Note the time, the 21 second mark in the video.
And then, when he is completely gone, it is still the 21 second mark.
So, in a fraction of a second, he was gone. And to show you how small the fraction was, note that the 21 second mark continues as this:
We're still in that same second. So, how fast did Oswald fall, and how could he fall so fast? Really, it was like he was vacuumed down. It's like a cartoon as you're watching it. He goes down as fast as Wile E. Coyote when he realizes that there is no ground underneath him.