Looks great, thanks for the link!
If you want to do an upgrade for the next show, you could swap out the Teensy 3 with a Teensy 4, and either upgrade to the SmartLED Shield for Teensy 4 or use this adapter and solder some headers/sockets so that you can use your existing shield. The Teensy 4 has enough power to refresh the panels much faster. You’re likely refreshing around 120Hz with the Teensy 3, maybe lower. The Teensy 4 will do 240Hz by default and higher if you set the refresh rate manually. That way there will be more lines refreshed in the shutter time of a camera, and the picture displayed will look more complete on a camera.
Here’s an article @marcmerlin wrote which includes how he improved his wearable LED panels to look better on camera (search “refresh”).