So the situation is now finally resolved.
I had been pushing to get an employer reference for right to rent as that is what the tenant wanted to produce. After a week or so I received it from the tenant directly, sent back to the employer using the email on the letter to confirm it is genuine and the employer replied stating they don’t know that person…
I’ve rescinded the tenancy as it unravelled the referencing report and reported tenant to action fraud.
I am though very surprised that rent guard were happy to accept an employer Reference sent from a personal email address as valid. Comes to show that going forward I’ll need to be doing a lot more of my own checks and not rely on rentguard to do the due diligence.