According to his medal index card, John Wilkie Stoddard was a Captain in the Prince of Wales Own (West Yorkshire) regiment. If it's the right man, he was born in 1883 in Oldham, Lancashire, and in 1901 was attending St Chads College, Denstone, Staffordshire, and by 1911 was living at Banstead Hall, Banstead, Epsom, Surrey and working as a school master. He seems to have died on 15 December 1933 while working at Flete House Preparatory School in Westgate-on-Sea, Sussex. His place of death is given as Southern Railway Bridge, Linchmere, Sussex, and there are a number of newspaper articles related to the circumstances of his death on the British Newspaper Archive, and by extension Find My Past. John Wilkie Stoddard's officer's service file is available at The National Archives, but it has not been digitized so an in-person visit would be required to view his various postings and movements.
https://discovery.nationalarchives.gov.uk/details/r/C735842 There is a Harold Gilmour Wylie serving as a 2nd Lieutenant with the 3/4th Battalion of the Royal Scots Fusiliers, born on 16 November 1896, but he also has a pension index card, and what is listed as his medal index card isn't very helpful in terms of the dates shown on it. The individual at the rear of the canoe, however, looks to be considerably older than 21/22, which is the age that he would have been at the time the photograph was taken.
