Bill,
If the California architects were building the "California" or "Lace Edge" bunkers before MacKenzie's arrival, either in print or in person, I think prudent men can conclude that MacKenzie had no influence.
And, if MacKenzie and others, contemporaneously, credited Thomas, Bell and others with designing a course, prudent men can again conclude that MacKenzie had no influence.
The preponderance of physical and written evidence indicates that the "California" bunker style was in existence in California prior to MacKenzie's presence, in print or in person, and there's NO documented evidence indicating that MacKenzie influenced, directly or indirectly, the bunker style in California, pre 1926 and 1921.
You want MacKenzie to be credited with influencing the bunker style in California, despite the lack of any physical or written evidence supporting your claim.