I cannot see why you have eliminated the chap who died in July 1928 and is buried at Waverley. Afterall, Merlin had clearly provided you with the MIs which show he was widowed back in 1893. I also cannot see where you have followed up re Herbert's father ..... perhaps he was Jack ?
ADD
NSW BDM online index will likely provide you with the names of Herbert's parents.....
I wonder how you are recording any of the information that many of us have sought out for you.
Cheers, JM
Herbert J's parents appear to be John B Steel and Louise E ( 5100/1932)
NSW DEATH REGISTRATION TRANSCRIPTION REF NO: 1928/12888
NAME John Steel
DATE OF DEATH 31st July 1928
PLACE Mater Misericordiae General Hospital, North Sydney, late of Redfern Street, Municipality of Redfern
RANK OR PROFESSION Saddler
SEX AND AGE Male, 67 years
CAUSE OF DEATH Lobar pneumonia
CERTIFICATION HD Ashton (registered)
DATE LAST SEEN 30th July 1928
FATHER John Steel
OCCUPATION Labourer
MOTHER Bridget Kelly
INFORMANT HX Steel, son, 40 Excelsior Street, Leichhardt
REGISTRATION Chas Saunders, 31st July 1928, North Sydney
DATE OF BURIAL 1st August 1928
PLACE OF BURIAL Roman Catholic Cemetery, Waverley
UNDERTAKER Joseph Medcalf
MINISTER AND RELIGION Antony Grealy, Roman Catholic
WITNESSES William Dreves and Arthur Bicknell
PLACE OF BIRTH NSW
TIME IN AUST COLONIES No entry
PLACE OF MARRIAGE NSW
AGE AT MARRIAGE About 24 years
NAME OF SPOUSE Elizabeth Agnes Radcliff
CHILDREN OF MARRIAGE William J 40 years, Henry C 38 years, John B 36 years living, none deceased
OTHER SUGGESTIONS OR NOTES None stated