A very intriguing case isn't it!
The records of his wife Mary's (MSW) 1868 petition for divorce gives time-line as you say:
* In August 1866 a Mrs Martha Mary Murray , a cousin of GGW came to live with them at Webb Street (separated from her husband) and Mary began to notice "undue familiarisation" between them - she suspected & was 'told' adultery. The quarrels led to Mrs Murray being told to leave , after which GGW became violent, ill tempered & physically abusive toward Mary and destructive to the house.
*They separated 17 Dec 1866 after GGW proposed it, and a mutual agreement was dictated by GGW which daughter Amy transcribed and GGW & MSW signed. He was to pay her 30 shillings per week for life - as long as she didn't disturb or molest him, and nor he, her.
*Mary was told in abt Nov 1866 that he was committing adultery - and did so first at Webb Street when Mary was not at home, but the children were ( Martha has put them to bed). From abt 9 Dec 1866 Mary said GGW was living at his address at Peel Street Hotham, and cohabiting with Martha as man & wife, committing adultery,
*In June 1868 GGW was in arrears of his agreed payments, owing 21 pounds and 10 shillings and when she asked him to pay he refused and as at time of petition for divorce, has not paid anything.
On 19 Sep 1868 Mary petitioned for Divorce and it was granted October 1868. He was ordered to pay costs.
Family:* Two surviving children at time of divorce: Amy Louise Wise (age 17 and wife of George Jame Stearns) born Adelaide 26 Feb 1851, and Reginald Steele Wise (aged 11, born Swan River WA 9 Jan 1856)
* There were other children who died young - one was Chapman Bassett Wise (1849-1850) who appears to have been named after GGW's brother Chapman Henry Wise, JP whose wife was Josephine Octavia Steele.
http://www.thetreeofus.net/19/175613.htm* Amy was only 17 at time she married 24 Dec 1867 - and her groom was only 20 - both were given written consent by their respective mothers, their each fathers stated to be dead.
* GGW mother: Eliza Wise, relict of George Wise, died 4 Jun 1871 at Hobart town, aged 68
(I can see the February 1869 death of the George Wise, age 46, bookseller - son of George Wise & Helen Dove:
https://www.findagrave.com/memorial/149044925/george-wise )
What is intriguing though is this:It looks as if, after George Gordon Wise was compensated for his loss of position in Swan River (per Mary's petition) that he bought the property at Webb Street in Fitzroy, VIC? He's listed as the Rate payer & owner at Webb Street up until at least 9 Jan 1867:
George G Wise, Civil Service, owner, Brick 4 rooms, Gross rates 33/16
( 'neighbour' ratepayers Flintoff, Cooley, Davis)
Then on 15 Dec 1869:
Mrs Wise ,
widow, owner, Brick, 3 rooms
33/16, annual Gross. Arrears 15/4
( 'neighbour' ratepayers Flintoff, Cooley, Davis)
So if he was definitely (?) alive in June 1868 when he refused to pay Mary her due- did he die between then and December 1869? If she became the Ratepayer/owner are there records showing this change of ownership?
In the divorce, what part of all that doc, proves the respondent GGW is actually alive? (genuine question - I might have missed it)
Re: Peel Street - it seems to be a rented 2 room house - From Trove:
At an event surrounding the attendance of the Duke of Edinburgh
23 Nov 1867. Stewards, include: Mr G. G. Wise, 28 Peel-street, Hotham
Feb 1868 - Wanted Servant Girl 12 or 14, for 28 Peel St, Hotham
23 Dec 1869 - The late Captain Thomas Devine,……..funeral from his late residence 28 Peel Street Hotham to Melbourne General Cemetery
Curious, as to what was the 1868 reference to a business?
Cheers
AMBLY