VB6/VBA appliication for Whatsapp management

I'd to make small routine (no software with user-interfaces) to allow users (a company that manage BUS) to send and receive WhatsApp messages inside our actual VB6 application. VB6 source code of actual application cannot be shared. The current application manages Damages, allocations, customers, ... and the company wants add a WhatsApp functionallity inside the actual application (not outside) to call the bus-drivers, send messages, maps pictures, .... and receive by the bus-drivers feedbacks, news, new opportunuty, ... For example: * to driver1= give us your position * to driver2= send a picture of damage * to driver3= write your driver licence code .... See the attached schema. Each desk into headquarter has an own mobile number. It's no possible to use QR CODE to sign-in. In attachment an example of message received by driver. Deliver of this project should be a source code only... to enable us to implement the source-code inside our software. No interface is needed. This means that I ask for VB6/VBA source code only, not compiled. Points of attention: bus-driver are more than 2, this means that new VB6/VBA function has to manage 3 (or more) whatsApp number/account in the same application (possible problems with multiple login/auth process WITHOUT using QR CODE and INSTANCE_ID, CLIENT_ID, CLIENT_SECRET). The routine must be able to manage multiple WhatApp accounts. No upfront and source-code required to test the routine. Not needed back-end management and DB management Previous experiences needed on VB6/VBA.