I also found the Louis Edwin's in Tasmania you mentioned and searched their family trees a bit but they were both false leads.
Hi
I'm not quite sure what you mean by "false leads".

In taking a closer look at some of the trees in which Louis Edwin (or Edward) BIRCHALL appears, he is only listed because he is known to be the son of Charles BIRCHALL ... (and a sibling to someone else appearing in a particular tree). That there is no additional information for him merely suggests that the tree owners are not actively researching the line of this Louis.
It may however prove difficult to learn more about the Louis Edwin BIRCHALL who died in 1892 as Tasmanian death certificates of that era, appear to offer scant information.
[Apparently the names of spouse and any children are not listed and nor is occupation of the deceased given ? ]
Have you checked Tasmanian indexes at all ... say for the supposed marriage of this Louis to a Mary Ann in 1870 ?
Or other records to establish what became of the child Charles Edwin BIRCHALL b. 1869 ?
[It does seem somewhat peculiar that the informant to Harold's death should "mistakenly" also supply the names "Charles Edwin" ... ?? ]
~ Lu