My first guess would be that this Orkney version was learnt directly or indirectly from Ethel Findlater. There are some differences of wording from her version, but from the sample you give it looks very similar.

The stanzas that that are most suggestive are 19 and 20, where the two singers' versions are identical. In 19, they reverse the order of the two couplets and have a different wording for the couplet about the island, which results in losing the rhyme. And they have "yard's arm" in line 4, instead of what seems to be the more usual "yardarm" (or just "yard" in the Deming text). And in 20, they combine lines from Deming 24 and 25, with repetition of the "poor injured ghost" line.

On the other hand, in stanza 2 this version has "If a maid is not coy they will her disdain", which is the line in the Roxburghe text, while Ethel Findlater has "When a maiden proves kindness they quickly disdain", which is close to Deming. So, once again, things are not so simple.

Any clues in the book?