Common misunderstanding. The rectifier board does not produce 5vDC for the MPU, the Solenoid driver board does. Voltage travels from the rec. to the SDB…. I would check the test points on the SDB, board in the upper right of the game. If they are ok, check them at the MPU.
The LEDs on that board would suggest the voltages are ok but I would test them to be certain.