Even though I have no problems creating tickets and automations that send a notification to the requester when the ticket comes via Facebook messenger, I cannot do the same if they come through Whatsapp.
Your support tells me it can't be helped at the time.
This is very inconvenient, since I can't establish automatic messages (via triggers) for messages that get received out of working hours, satisfaction rating request, and so on. I can only set one general automated message for all incoming Whatsapp texts we receive, which is not for specific purposes and doesn't help so much.
There doesn't seem to be a logical reason for notifications via trigger in Whatsapp not to work, please fix it.