This is from Bob Beck and Nick Leefe's info:
Jan. 20th – arrived NYC on SS Homeric on way to California (ST)
Jan. 28th – arrived San Francisco (ST)
Feb.11th - Meeting in SF on Meadow Club (ST)
Feb. – received Cypress Point commission (S-CP)
March – Reconstruct MPCC, Cypress Point viewing (W, H)
March – to Meadow Club (D, H)
March - Early spring to Southern California, consulted on Redlands CC (S-CP)
April – played at Midwick CC on his way home (W)
May/June – Met with Maxwell, Melrose Park (DHS)
May 19th – Alwoodley: Match v Ilkley [16] (DHS, AL)
June 3rd – at Walker Cup, St. Andrews
June 8th Leeds at Alwoodley Committee Meeting.(AL)
June 16 Alwoodley: Remainder v West Riding Club Members[17] (AL)
Summer: redesigned the 8th and 13th greens at Pebble Beach (S-CP)
Cork – returned from America (DHS)
Lahinch (DHS)
Mid September: Alwoodley: M played in match with Yorkshire (AL) (W)
Sept. 19 - Left on round the world trip on the SS Ontranto of the Orient Line (W H)
Oct. 25th – arrived Melbourne, Australia (DHS)
Nov. 11th still in Australia, consulting, Royal Sydney (DHS, H)
Most of the early information is the result of Sean's (ST) excellent research. It appears Meadow C was his first project. The Melrose visit must have been April or May '26 (really a Maxwell project).
I'm not sure what the original source of that Behr-MacKenzie photo was...I don't recall seeing it in an old magazine. You are probably right about the occasion, '26 Walker Cup, although it could also be the British Open in '27 - MacKenzie attended both. The question still remains when and where they met.