Andrew Wilson was definitely the tenant at Berryleys at the time of that Christmas card; he appears a lot in the newspapers, and quite easy to track.
The following is Andrew's obituary from Aberdeen Press and Journal, 07 October 1914. Maybe something in it will help connect Andrew Wilson, or a family member, to Mr. McCulloch.
Death of Mr Andrew Wilson, Haughs, Keith
The death took place yesterday morning of Mr Andrew Wilson, farmer, Haughs, Keith, in his 85th year. Mr Wilson, who had been ailing for some time, was born at the farm of Corsairtly, Keith, which his father, the late Mr Andrew Wilson, occupied for a considerable time, and carried on an extensive business in the manufacture of lime at Douglas Brae Lime Works, since disused.
Mr Wilson, Haughs, at the age of 25, entered on a lease of the farm of Montgrew, Keith, where he remained for 27 years. He then went to Berryleys, also on the Fife Estates, Keith district, and farmed it for 19 years, and 16 years ago he proceeded to the farm of Haughs.
Deceased was a devoted member of the old U.P. Church and leaves two sons -- Mr Andrew Wilson, who farms Copperhill, near Elgin; and Mr George A. Wilson, who manages Inchgower Distillery, and is now Major Wilson, of the 6th Gordon Highlanders (T.F.),, and is at present stationed at Bedford; and four daughters, one married to Mr George Davidson, banker, Rothienorman; and another to Dr McCallum, Kendal.