Your log only contains the MCU 'mcu' shutdown: Missed scheduling of next digital out event error, but not the one from your screenshot. In any case, both typically have quite similar reasons. Usually and unfortunately, they are tedious to diagnose, often due to subtle hardware instabilities or effects from third-party modifications.
See:
Edit:
It makes sense to remove the modifications and upgrading Klipper to the latest Git version as it contains extended CAN diagnostics.
A new log would be required after any changes.