Edward Charles Man was reported to have gone to Australia after an argument with his father and never heard from again.  However for the 1891 census for the county of Norfolk, three individuals with the last name have been found, all in Norwich, and they are:

Charles Man, 32, born Clapham, Surrey, Boarder, Student
Frederick Man, 29, born Clapham, Surrey, Visitor, Colonial Broker Agent
Edward Man, 38, born Clapham, Surrey, Head, Classical Schoolmaster

This Charles was the right age to be Frederick Man's son Charles Desborough Man  and Frederick was the right age to be another son of Frederick's, Frederick Henry Dumas Man.  Edward was not quite the right age to be the ' missing' Edward Charles, the son of Edward Desborough Man, but 'not right' by only a few years. Could this be our 'missing' Edward Charles Man?

On the print images of the census pages for the above Charles was shown as Charles D. Man, Theological Student, which is just what we know about him. So, Frederick's son without a doubt.
Frederick was shown as Frederick H. D. Man, Colonial Broker Agent. Again, Frederick's son without a doubt.

Edward was shown as Edward Man, Classical Schoolmaster. He is single and Frederick is visiting him. Even though the stated age is a little off, this must be the long missing Edward Charles Man. There's no way that Frederick "Bob" Man would be visiting an Edward Man born in
Clapham if he were not his cousin.  

The scenario that is now painted is that Edward Charles argued with his father because he was not interested in pursuing the sugar brokerage profession, but rather wanted to be a scholar. Maybe he did go to Australia originally but, if so, he came back and pursued a career as a
classical schoolmaster.

A look-up volunteer in Norwich searched the City Directories and came right back with a hit for 1892, but not 1883, nor 1896 (these were the ones that he has). For 1892, the entry was MAN, Edward Kirkman M.A. (sub-master of Grammar school) School Lodge, The Close.

That 'Kirkman' was odd,  but then if one recalls Edward Desborough had a sister who
married a William John Kirkness. They lived in Forrabury, Cornwall.  Supposing Edward was trying to disguise his identity and had made up that middle name from KIRKness and MAN?

Frederick was married at the time he visited his cousin Edward, so more than one person was aware of his existence. Interesting story ... to be continued.