Nearest I can get is 'Marybone' i.e., Marylebone, pronounced Marlebone. It could of course be Marlborough that was intended, not a million miles from Oxford.

Your burning question I'm not sure I understand. The answer is simple.
Very little material was collected/published in England prior to 1900. Baring Gould only collected in one small area in Devon/Cornwall.
Kidson collected only in Yorkshire and S Scotland and most of that was from friends and correspondents. Likewise Lucy Broadwood was much dependent on friends and correspondents. Not a lot of sweeping fieldwork and many of the songs did not appear until collecting started in earnest after 1900. Very little survives in manuscript form. Very few people were interested until Sharp started publicising.

Regarding the Orkney version, whilst many of the Wexford Girl variants were collected in places of Scottish settlement, Eastern Canada and NE United States, I don't think that's the connection here. Simple logic would suggest the Orkney version came back from the Eastern Seaboard. Orkney men were great sailors and many went to the fishing off Newfoundland and of course went whaling to Baffin Bay.