I can’t see a listing for your board in your printer.cfg.
There’s an mcu listed for the Pi but no listing for the board mcu ie [mcu] serial: /dev/serial/by-id/ Your board details
The hardware use USART1 PA10/PA9 connect to RK3328
serial: /dev/ttyS0
restart_method: command
The mks skipr board works via usart and in the example with github such a connection is prescribed and it worked like that, but then something went wrong