Sue you're an absolute star! I couldn't find any mention of him or Doris in Australia.
I notice on the Karachi trip he also gave his age as 50 so it would be nice if he turned out to have been 54 and born in 1882. THEN I reckon we have my man.
Hopefully the Islington birth certificate may have a birthday of 7th Feb 1882.
I found that William and Doris had had a daughter Mignon Beryl born 28th Nov 1926 in Bombay who died 4th Aug 1930 at Sewri. They may also have had Isabel Mary who died 29th May 1934 aged 1. Perhaps it was time to resign the Commission and move on.
It does look like they might not have had any more kids.
Unfortunately, it looks like his sister Elsie died a spinster 14th Jan 1952 in Beckenham, UK and left her all to a spinster Edith mary Chubb who was either the one who died in Hammers-Lane Hill 16th Jan 1955 and left her all to Norah Faith Chubb, spinster
or
the one who died 18th June 1959 in Bromley and left all to Minnie Victoria Chubb, spinster
Descendants looking sparse so far!
Will apply for death certificate
Have emailed YMCA Procter, Mumbai !!!