Need some help on a template condition

I’m trying to rework my ‘Welcome Home’ TTS announcements. Currently I have two automations for USER1 and USER2 that both look similar to the below.

- alias: Notification Audio - Welcome Home USER1
  trigger:
    - platform: state
      entity_id: device_tracker.USER1
      from: 'not_home'
      to: 'home'
      for: '00:02:00'
  condition:
    - condition: time
      after: '07:30'
      before: '19:00'
  action:
    - delay: '00:00:10'
    - service: script.turn_on
      entity_id: script.say
      data:
        variables:
          master: 'media_player.chalkboard_room'
          where: 'media_player.chalkboard_room, media_player.kitchen, media_player.loft'
          volume: '.5'
          what: 'Welcome home USER1.'
- alias: Notification Audio - Welcome Home USER2
  trigger:
    - platform: state
      entity_id: device_tracker.USER2
      from: 'not_home'
      to: 'home'
      for: '00:02:00'
  condition:
    - condition: time
      after: '07:30'
      before: '19:00'
  action:
    - delay: '00:00:10'
    - service: script.turn_on
      entity_id: script.say
      data:
        variables:
          master: 'media_player.chalkboard_room'
          where: 'media_player.chalkboard_room, media_player.kitchen, media_player.loft'
          volume: '.5'
          what: 'Welcome home USER2.'

What I want to do is add a condition to the USER1 automation that looks at USER2's device tracker to see if it just arrived home too. Then if it did, don’t fire the single user automation but fire a different one.

I was thinking I could use a template trigger to look at the .last_changed attribute of the state, but that doesn’t really tell me that they arrived home at the same time.

So really it needs to be:

  1. Automation that welcomes USER1 home (assumptions: USER2 is away, USER2 was already home, USER2 didn’t just arrive home)
  2. Automation that welcomes USER2 home (assumptions: USER1 is away, USER1 was already home, USER1 didn’t just arrive home)
  3. Automation that welcomes USER1 and USER2 home (assumptions: USER1 and USER2 just arrived home together)

I think the state trigger example on this page, might be a good starting point: