@knutselsmurf there is no easy fix, because you need two separate UARTs to drive the PanelDue and the Neopixel board, and the only user-accessible UART on Duet WiFi is the one connected to the PanelDue port.
Could you just add which of the two chipsets that display uses? ST7920 or ST7565 iirc.
The Mini12864 uses the ST7565. Displays with the ST7920 such as the reprep discount one are natively supported without the need of a dedicated wiring loom.
