Here’s my working config, it’s also behind reverseproxy but i’m using caddy but that shouldnt matter. Can you enable debug logging for the google-assistant integration? The trick for me was to disable both report_state and expose_by_default as well as linking HA through the google assistant app and not through the google home app. Also check the permissions fo the service_account and the api-scopes. Also check for logon tokens, and clean them in HA
Here’s log settings, google_assistant.http should be enough:
GA Config:
GA Entities:
Caddyfile: