Could you please add lip-sync data in response with VAPI-Assistant (
https://github.com/DanielSWolf/rhubarb-lip-sync)?
As the above mention linked, help for that but, If we get the same data from Vapi's side then many business continue Vapi's service.
If we get the lip-sync data as well, we can add a virtual avatar and create a more elegant application, as our client is requesting this feature and many developers are looking for the same.