Mystery solved! For anyone following along on this quarry I will just tell you that one savvy user of FindMyPast has found in one military record the following, which I still can't get to come up in MY search of FindMyPast but it brings me the answer I was hoping for:
First name(s)    Alfred Ernest Albert
Next of kin    son of the late Albert Harragin
Last name    Harragin
Country    Trinidad & Tobago
Rank    Captain
Notes    later Major; MC awarded for gallantry at Damieh Bridgehead, Palestine, 22 September 1918
Battalion    1st Bn
Year    1914-19
Corps    British West Indies Regt
Record set    Caribbean Rolls Of Honour WW1
Contingent    1st Public Contingent
Category    Military, armed forces & conflict
Departure Date    18 September 1915
Subcategory    First World War
Troopship    HMT Verdala
Collections from    Americas, Caribbean
Honours    MC
And since then, some other things have come together that give me his mother's name, as well as the names of his wife and children. In addition, I have a family photo. As a side bonus, my search has connected me with a cousin doing research on my own paternal family line still in Trinidad. So, happy days! Thanks all.