Have you managed to locate any Passenger and Crew records for your Thomas (other than the 1901 census record)?
Anything to confirm when he first arrived and/or permanently settled in the UK? Perhaps a previous marriage, as well?
TIP: You can also try researching the vessel he was on in April 1901 (Dunearn). According to the Shields Daily Gazette (6 March 1901), "The barque Dunearn was discharging her cargo of grain in Tyne Dock from San Francisco. The Dunearn has had an uneventful voyage of 151 days, calling off Falmouth for orders ..." So if TM was on that 151 day voyage, he would've been in San Francisco in late 1900.
Does his 1922 marriage record give his home address? If so, have you tried researching it, in case it throws up any clues you can use?
Also, who are the marriage witnesses? Could either one be related to him?
We welcome any query on Who When Where. If you have previously posted it on another forum (including the old WDYTYA forum), please state this in your opening post - this will save people redoing the research which has been done before: they can look at it and possibly go further with it.