I wonder whether Hugh is the H W Painter (AB), 26, of London on a crew list from London to Sydney arriving 20th Sep 1896? The vessel was the Mount Stewart, of Aberdeen.
There's also a later record for H Painter (AB), 31, of London, on a similar crew list (the Port Jackson, of Aberdeen) arriving Sydney 17th Sep 1901. If this was him he cannot have been long dead when Mary Helena remarried on 13th November 1901.
Possible birth reg as Hugh William Painter, Mar qtr 1869 Camberwell. The record of his 3rd Jan 1869 baptism shows birthdate of 6th Dec 1868 - parents George John (butcher) & Elizabeth Keziah.