Watching this video, it seemed after the highlighted point in the video that black was doomed, but from my view it was just materiel? After the exchange, white would have taken a rook and the queen (and trading white's own queen) leaving black only a bishop vs. two white rooks. Is that why black resigned? Obviously at that point black would have been at a big disadvantage. But I'm curious if there was a compelling mate opportunity for white above and beyond the materiel advantage. Here's the video:
https://youtu.be/APJ5E1wXB3g?t=1631
(Also, I'm confused why the YouTube video refers to this as a "Queen sacrifice" since the queen wasn't in fact sacrificed?)