A quick search of records for Mr. Wilkins Junior and Mr. Wilkins Senior turned up the following.
Mr. Wilkins Junior married Kate on 25 August 1886. His name was listed as David Wilkins as was his father's name. His father's occupation was listed as "Steward"
David Wilkins Senior married Sarah Bryant in 1855. On the marriage banns his name is listed as David James Wilkins. In 1857 David James Wilkins was listed as a Ship's Steward on the church record of his son, David James Wilkins, baptism. On the census of 1861 David Wilkins, Senior was listed a Captain's Steward, R.N. In the records of the 1899 Probate there is a David James Wikins of Cape Town, South Africa, ship's steward, died in or since 1877 at __________, widow Sarah Wilkins.
This all corroborates the newspaper article. If David James Wilkins, Senior did serve in the Zulu War it would have been in one of the colonial units.