"So this is confirmed - there was someone, and apparently that someone has not come forward.
IMO Suspect#1 ...."
And further to your comment Marple, most likely why the police are desperate to obtain and read that last message on Whats App between Theo and the unknown.
I thought originally it was said though that with Whats App they can see a user to a user, IE who sent who a message or a phone number sent a message to another phone number, they just cannot read the message sent due to encryption?
It was confirmed that Whats App were cooperating with police and had handed over information however confirmed that they are unable to provide any messages sent de to the encryptions, even if they wanted to.
Do you consider your referal to suspect #1 could be the mystery Whats App person and may be the person that could have been with Theo that night?
From this below article / link they discuss what information they can provide with their terms of service.
WhatsApp assisting police in Hayez investigation – Echonetdaily
‘We understand the important work being carried out by law enforcement and are assisting them in accordance with applicable law and our terms of service.” – WhatsApp spokesperson
‘In this case, we have provided information to international law enforcement officials,’ they said. ‘While we can’t access encrypted conversations, end-to-end encrypted platforms do have some limited information about users that they collect in order to provide their service.
WhatsApp has published
Information for Law Enforcement Authorities that outlines the kinds of information they can disclose when they receive a valid legal request. ‘This may include (if available): name, service start date, last seen date, IP address, email address, profile photo, numbers blocking or blocked by the user or other basic subscriber information about the account, not including the contents of communication.’