I haven't used any ring devices.  However, if the Ring doorbell is capable of creating events (i.e. motion detected, doorbell pressed, etc.) within the Amazon Alexa ecosystem, then you should be able to trigger routines with these events.  Then, in a routine, you can turn on a light that is defined in the Crestron voice modules and from that trigger code on a Crestron processor.  Since Ring is already working with cloud services, to send notifications to your smart phone, etc., there really isn't any downside to leveraging Alexa routines. to help you integrate with your Crestron processor.

Hope this helps

Jay