As far as I know R.B. Moore was not working from primary sources, he relied on published material.

Following Frances's observations, the point about Jenken More was gone into by Jim Roscow in his piece on Corbes (Proc IOMNHAS Vol X No 3) I would also refer you to
Talbot's Transcription 1511 as the former tenant of lands in Braddan, he probably held Kirby or Ballakilley before it became Ballafletcher.

The James reference is suspect to me, subject to anyone knowing better, I do not believe the name James was in use here at that dat

Cannot you tell us what your actual connection is, these links are surely speculative?

NGC...