Hi Jefferbob,
So to be able to use Alexa (which will be fully Skills enabled on October the 1st), Alexa has to run through your phone as the 422GW itself has no internal data/Wi-Fi feed. This is why the audio is always played from your phone, even if it's controlling your Dash Cam, to avoid confusion for the user (for instance putting your mobile inside a bag in the footwell, then wondering why Alexa isn't responding because the camera is 1ft away).
If you don't want the audio played directly from the phone, you can enable the Bluetooth to talk to a separate external speaker, however if you're using a Bluetooth in-car system for hands-free phone calls, that will no longer work.
The only other thing to do would be to un-pair the Bluetooth between the phone and your car, however then the sound would come directly through the mobile phone.
I'm sorry I can't offer another alternative.
Regards,
Millie- Nextbase