hi linda, if you defined all of these people in wikitree and referred to their profiles in your question it would be much easier for people trying to help you, to follow exactly what information you have already and to target their assistance better. If you have one of the census returns for Thomas as you say where did he report his birth to be on that (although I can't find any 1911 census return with a Thomas Winn as a shell tester in London)?
I'll try to help based on what I understand of the information provided...
Thomas & Rose married in Wandsworth, S London
Groom: WINN, Thomas W
Bride: ELY, Rose
Registration district: Wandsworth
Year of registration: 1917
Quarter of registration: Oct-Nov-Dec
Volume no: 1D
Page no: 869
The marriage certificate with Rose will give you an age that may be useful to filter the many TW Winns around London.
Possible births for Thomas W Winn in London (he was likely similar age to Rose but no younger than 18 in 1917, so 1870-1899)...
WINN, Thomas William, St. Saviour Southwark, Q4,1871, Vol:1D, Page:51
WINN, William Thomas, Fulham, Q1, 1878, Vol:1A, Page:214
Possible prior marriages for Thomas...
WINN, Thomas William, St. Olave Southwark, Q3,1904, Vol:1D, Page:335 to either BOTTOMLEY, Elizabeth Florence OR HILL, Elizabeth Wood
WINN, Thomas W, Islington, Q3,1913, Vol:1B, Page:880 to LEWIS, Sarah J
Possible deaths for Thomas - only two Thomas W Winns born 1870-1880 died in 1917-1960 in England...
WINN, Thomas W, Croydon, Surrey, Q4,1927, AaD:55, Vol:2A, Page:299 <<==this croydon death looks likely
WINN, Thomas W, Sedbergh, Yorkshire, Q1,1937, AaD:62, Vol:9A, Page:1
How certain of Rose's original maiden name are you? The only Rose E married to an ELY that I can find is this one...
ELY, John Dawson, Brentford,Middlesex, Q3, 1900, Vol:3A, Page:233 to SELFE, Rose Ethel (or JACKSON, Emma Delta)
as well as the marriage record they are visible in the 1911 census...
ELY, John Dawson Head Married M 37 1874 Mercantile Clerk London Hampstead
ELY, Rose Ethel Wife Married10 years F 33 1878 Somerset Bristol
ELY, John Dawson Son M 7 1904 London Hampstead
ELY, Talfourd Ernest Son M 3 1908 London Hampstead
ELY, Brian Desborough Son M 1 1910 London Hampstead
HUMBY, May Servant Single F 21 1890 Nurse Domestic Hants Romsey
RG number: RG14 Piece: 648 Reference: RG14PN648 RG78PN22 RD8 SD1 ED58 SN203
Registration District: Hampstead Sub District: Hampstead Enumeration District: 58 Parish: Hampstead
Address: 31 Crediton Road Hampstead County: London
There are too many Thomas W Winns living in England around this time to be sure which one yours is based on the info provided.
I hope that this helps