Can someone explain the final board status of this game to me? Black's resignation makes me think white's move kills the top group, but I don't see it. Black looks alive to me.

I think the move makes the J14 eye in sente and so white is alive and black doesn't have enough points, but I could be wrong.

That makes sense, thanks. I was thinking so hard about how white could kill, without realizing white didn't need to kill...

The key moment was earlier, when white resisted e14 by answering at f13 and destroying the points in the e12 area instead of safely connecting at f15 (though I'm not even sure black would win that way, the game is closer than the error in my quick counting). The following moves were just white demonstrating the correctness of his reading that he could resist and get cut and still live with his big group.

P.S. Lots of nice sabaki play from Chen in that game, he really is a master of defence.