1. Until the Harvester Case the wages for a fettler with a family would not be likely to support TWO separate households, and even with taking into consideration the Harvester Case, it is still unlikely there would be sufficient funds.
2. DAVIS is often recorded as DAVIES in many records, and so you need to consider all George Henry DAVIES chaps as well as George Henry DAVIS.
3. It was NOT compulsory to enrol to vote until the mid 1920s, so just because you cannot find someone in NSW in pre WWI does NOT mean there was no one to find.
4. Until you have had experienced eyes to compare the signatures you simply do not know if the chap who married your lass in 1907 was actually a fair dinkum George Henry DAVIS going about in his parents locality, marrying a local very friendly lass, who may have met him on the street in Forest Lodge where Mrs (Minnie) George Henry Davis lived. It is just as possible that the Rev Jeannings was not familiar with the DAVIS family so took the chap's word that he was George Henry Davis.
5. Without the marriage of Oct 1907 being found by a court to be flawed, the offender in the 1919 marriage (if the same person as Oct 1907) would be Jessie. It would therefore be sensible for you to clearly, beyond all doubt (not just reasonable doubt) establish if the 1907 marriage is flawed in any way. Afterall, you don't want to pass on information to your family that would be WRONG ..... or mis representing your shared ancestors for "what does that say about your research skills".
6, Major difference between being a labourer and being a farmer. I have picture somewhere of a Diary farm at Glebe Point in 1930s.
There's just some of my thoughts.
Cheers, JM