I solved opening the garage door when leaving by a much simpler approach: “Alexa, I’m leaving”(regex for various phrases) along with an Aqara button if I was on the phone.
For arrival of my car only, and not triggering when I would walk nearby (park and beach 1 block in either direction), I had home assistant dialed in to notice the Bluetooth connection to my cars audio by its ID from within the app etc. along with the proximity and whether I was moving towards or away. Away would close and towards would of course open. This was particularly tricky but as you explain always failsafes in place: garage door opener in car and for the opening mechanism was set to close in 2 mins but reset if there was motion in the garage. If I was marked away and there was motion in the garage it would close and also sound an audible alarm.
None of those of course would have been possible without NodeRed. It’s so much fun to use.