Samsung G75F firmware update broke capture card

I bought a Samsung G75F 40" a month or so ago. Great monitor, but sometimes it's finicky with some inputs. I saw there was a firmware update, and hoped it would help. Unfortunately the opposite happened.

I use an Elgato 4K X, their new top of the line USB-C capture card, to stream Switch 2 games. With this update, a setup that used to work properly no longer does. The Elgato can capture the video, but the monitor no longer detects the passthrough video at all. This makes streaming nearly impossible, as I don't want to live with major video lag.

The old firmware was 1000.1 or .2. The new firmware is 1001.2. Don't update!