How to use Pendo on a Whatsapp chatbot

Hello. 

I am new at Pendo, and need your advice.
Our main service is a WhatsApp chatbot that integrates different APIs and functionalities to provide users with services, information, and payment methods.

As it runs behind the front-end channel, we cannot install Pendo in WhatsApp itself, capture Whatsapp events, or have a URL or App page. How could we use Pendo with our system (.NET)?

Is there some way? what could be the constraints or boundaries?

Regards!