I would check the door switch with a meter and replace if it was at fault.

Take a look at your old post and download and print the wiring diagram.
I am hoping that this diagram applies to your 2000 even if it is for a 2001.

Your switch looks OK.
A is common so when B is open C should be closed and vice versa.
Also you are looking for a closed circuit which is keeping the motor on, not an open circuit.

Perhaps going through the circuit path when the motor is running will help.
Start at Neutral.
The door switch is as shown when the door is closed. (C to NO) closed).
Then along the GRAY wire to M6 on the motor.
The centrifugal switch in the motor as shown is in the off position. So when it is running the shown open contacts are closed.
This removes the START winding from the circuit but the RUN winding is connected.
Power then flows through the RUN winding to C on the timer.
Then through the C/B contacts in the timer.
B is L1 (120 volts).
So that is the complete circuit from Neutral to 120 volts for the motor when running.

Something must be shorting Neutral to the M6 motor contact for it to keep running with the door open.

How do you turn the unit off?
Once off how do you re-start it?
Do you turn the timer to a cycle and then still have to use the push-to-start button to get it going?
Has this unit ever worked correctly?
It is almost like someone has messed with the wiring.