BarbaraG,
Welcome to the forum and may I compliment you upon your interesting research. In the distant past, circumstances dictated that I travel from time to time to nearby Broadway and stay in its hotel there. What a lovely area. As regards the officer's death in Southport, I am reminded that the poet Wilfred Owen, of the 5th Manchesters, did training in that town, but later during the war.
PhilipG.