When all members of your group are outside of a location, this Applet will trigger an Alexa Action By Mkzense.
If
Last member exits an area
This trigger fires when the final member exits an area, meaning all members have left the area.
Then
sendAlexaActionByMkzense
This service from mkZense will send an action to run a routine on your Alexa device. Use it to add Voice to your Applet.
Discover more time saving integrations for Alexa Actions by mkZense and Group Location