Looking back through the communications with the family member the original posting does need some clarification. I see the point you are making.

A better summary of the discussion:
Both Model 11's belong to one of the brothers who also made the knife on the right while visiting the shop when he was a young kid. They were not intending to claim that the knife on the left was an early pre-production.

Here is the exact wording from the family member's response:
"A Model 11 and one of the original preproduction prototypes of the Alaskan Skinner. 1952"

My mistake - Sorry for the confusion.