Emails were sent from Lynda Spence's account to someone known as "Uncle Ben", said to be in Qatar, and "Adam Grange", said to be in London, copying in an accused, Colin Coats.
The High Court in Glasgow heard that the address for "Uncle Ben" was set up in March 2011, using the broadband internet connected to the Rio Cafe in Partick, Glasgow.
Derek Ogg QC, defending Coats, asked witness Detective Constable Terry Graham if he was aware the Rio Cafe was known by her friends as "Lynda's Partick office".
The detective said that was correct. It was agreed by all parties at the trial that emails sent and received by "Adam Grange" were accessed using a connection at PC Pixel in Great Western Road, Glasgow.
Mr Ogg said: "'Uncle Ben', 'Adam Grange' and Lynda Spence are all one and the same person, isn't that right?" DC Graham said: "Yes."
Emails were read out, which was a conversation between Coats and a solicitor "Uncle Ben" had claimed was organising Ms Spence and the accused man's "power of attorney".
However, a reply from the solicitor said the firm knew of no one named Ben from Qatar.
Coats, Philip Wade, both 42, David Parker, 38, and Paul Smith, 47, deny murder. The trial continues.