Hi Chris
I don't know whether this will help but in 1901 I have found the following Henry Argents (there are more but ages are too far out) and this assumes he wasn't mistranscribed

Living in
Bethnal Green: Henry Argent aged 43, a Scaffolder born Essex, his wife Sarah aged 45. Might this be the one died aged 81?
Living in
Camberwell: Henry Argent aged 55, his wife Sophie born India and huge extended family - age is out and he works for Wesleyan Assurance company
Living in
Camberwell, Peckham is Henry aged 42, a widower - occupation Plumber. Two sons, one is Henry aged 15, one looks like Prince

age 10 - wonder whether it should be Francis and the enumerator couldn't read the name when he wrote the sheets up

Henry's place of birth is given as Old Kent Road though ? However the rest of the details look promising, Henry's wife must have only died within the last 10 years.
What occupation do you have from his marriage certificate?
What causes of death do you have from the 'wrong' death certs?
Helen