Many places are listed under the GLEN abbreviation!
As Joyces Creek, where Jane was registered and Newstead are only less than 10 miles apart, I guess it would be a place in proximity to them.
Lots of immigrants "adjusted" their ages, especially those over 40, as younger workers were preferred.
Whether his death certificate recorded if his wife was deceased, might have depended on the question asked - what is/was his wife's name ? is she still alive? Most of the ones I have seen do say deceased, but you cannot just rely on it.
This is the abbreviations Page for place names for Vic BDM
https://bdmabbreviations.steveparker.id.au/
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