Getting the data onto the screen is fine, and IRL I can't see any flicker, but the OLED screen itself is apparently refreshing at something like 107 or 133 Hz.
One way to potentially resolve this is to place the setup in a darker place and/or add a piece of tinted transparent material in front of the camera. The camera will automatically adjust the shutter speed (not the frame rate) because of the reduced light to 1/30 or so which will allow more of the screen to be captured.
