Hey Sean,
I don't see much upper back rounding. I see a somewhat rushed setup on a few latter reps, but you demonstrate that you know the setup pretty well. Maybe you see something I don't.
I'm looking really closely to see what the wonky knee movement is. I think at 0:29, you actually manage to get your right knee out a little too far. Then it normalize on the ascent. Maybe someone more experienced can verify this, as I haven't seen many cases of too much knees-out.
Really these are very nice lifts.