Pull up on A8

[admin]

see this photo. S1, S2, S3, S4 ports all have pull up resistance on PCB.

But I am using the inputs on the top left ground to input off the one chip

[color=oklab(0.89908 -0.00192907 -0.0048306)]  - platform: gpio
    name: "Water Closet Door Sensor"
    pin:
      pcf8574: pcf8574_hub_in_1
      number: 1
      mode: INPUT
    filters:
      - delayed_on: 0.5s[/color]

Do these have pull up resistors?  I am seeing significant bouncing?

these port can't use pull up resistor. they are not connect with ESP32 pin directly. i suggest you test with S1,S2,S3 or S4 port.