Hm, but what if he altered his middle name to be devious?
Or, of course, changed his whole name in order to marry again.
There's a Hayward-Harrison birth in West Ham in 1918 (Anc'y helpfully has it as Marrison). And a Joseph C Hayward married Harrison in 1920 in Shoreditch, with a Hayward-Harrison birth in Shoreditch in 1922 (probably died 1925 Hackney). There's a Hayward-Harrison marriage in Hereford in 1913, but otherwise no marriage that accounts reasonably for that West Ham birth (barring remarriage for the bride, of course, always a good possibility post-WWI), and there are Hayward-Harrison births in Hereford in 1916 and 1923. The 1920 marriage could be Joseph Charles Hayward 1881 Hereford or 1883 Islington or 1894 Holborn ...
I wondered about a son who went by a middle name, but there are no Hayward-Wood births with middle initial G before 1928ish either.
The only marriage with the surnames of the 1927 birth that could fit, for time and place, was in Wortley in 1917 - there's also a birth 1921 Wortley. The wife had an unusual name (I have one in my tree) ... Oh aargh, that's a mistranscribed Nellie at Anc'y; far too many born in Yorkshire 1880-1900, so impossible to identify a remarriage or death.
Your JNH is the only person who accounts at all for the death you have, according to the births index, so it really has to be him.
I dunno, I think I'd look at the 1927 birth, 1962 marriage, 1994 death and perhaps the 1917 marriage, all in Bradford. Joseph may have loved his middle name, but if he had relocated and was marrying bigamously he might have chosen a whole new one, or he might not have married and simply partnered and had a child.
The electoral roll shows a person by the name of the wife in the 1962 marriage (i.e. who could be the widow of the 1927 birth / 1994 death person) living in Bradford to 2013. I don't see a matching telephone listing (the one in Bradford with the same initial is a different person, from a match on the ER). If you really want to solve the mystery of the informant on the death certificate, that person might be able to rule him in/out.