I have downloaded the birth certificate for Alexander-Gunn-Hay-Goodwillie.
It shows that he was born on 09 May 1890, in 11 South Guildry Street, Elgin.
His parents were William Hay-Goodwillie and Fanny Goodwillie, nee Gunn. They were married on 06 October 1882 in Detroit, Michigan.
I cannot find any marriage record for a Mary Ellen Mackenzie to a Alexander-Gunn-Hay-Goodwillie anywhere in Scotland.
Strange?