There are 19 "D. Macleod"s on the CWGC register who died in 1917, none on 19 July and none shown as aged 21. Do you have any other names or initials for him, or know what regiment he served in? Where was his home? All this would help to sort out the right one.
Another search, on the National Archives documents online index of medal cards shows 86 returns under "Donald Macleod", without other details...Difficult!
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