There is a Thomas Lundie age 32 b Lincoln on the 1911 census as a lodger in Chiswick with the Harriss
family. Mr Harriss may have misheard Lincolnshire for Lincoln when asking his lodger his place of birth when he had to fill in the census form. Occupation gunmaker's assistant, but it looks as though clerk was written first and crossed out. If this is the Thomas from Grimsby, it does put him in the London area just prior to marriage.
Yes we think that is probably Thomas from Grimsby. We have been sent a copy of a 1915 letter rejecting his application for a position in the Army Ordnance Department, which would tie in with him having some knowledge of gunmaking. The letter is addressed to T Lundie, 150 Brixton Hill. There is a similar letter rejecting his application to join the Royal Fleet Auxiliary.
These letters came from a family connection in France, who also placed him (presumably in military service) at Etaples in 1918, at Camiers in 1919, and in Abbeville in 1920. At present I have no further information from that source.
Regarding his activities in London prior to his marriage, there are newspaper reports of a Thomas Lundie aged 36 acting as doorman for an illegal casino at 92 Knightsbridge, raided by the police in March 1913. His occupation was stated to be "agent" and his address as Park Road, Regents Park.