I think (tentatively) I may have found him. There is a Charles John Rolls, retired, living in Parramatta from 1930-35, dying in the latter year. Now this Charles J Rolls parents are listed as Thomas and Mary on his death, and from that I can see he was born 1856 in Goulburn NSW. Now from family trees on Ancestry (I know) I've looked at this Charles J Rolls and it appears his mother took (some of) the kids off to Naseby, (the right area of the world) with another man! Two of this Charles' sisters most definitely married in Naseby and I've managed to trace their lives through the papers, and that of his rather scandalous mother, despite how ridiculous the family trees (i recommend looking at them) look it appears as though they're actually correct. Now the fact that the last electoral roll for Charles in NZ in 1928 and the first for a Charles in Australia is 1930, to me, definitely also helps the case. Now why he wasn't on any earlier rolls is beyond me, as is why he returned to Australia, but to me this sounds plausible.