The online Leach collection is indeed full of errors, as 'GEST' remarks. A particularly bizarre example:

Their commentary on '78-054 NFLD: Handsome Harry' originally identified it as a version of Roud 568 / Laws P34 ('Sailor and the Ghost'). It obviously wasn't, and a few minutes' work revealed it to be a completely unrelated popular American stage song of the early 20th century, originally published by George W Meyer Music Co. in 1913, as 'Always Take A Girl Named "Daisy" ('Cause Daisies Won't Tell)': music by George W Meyer, words by Alfred Bryan and Sam M Lewis.

The ludicrous mis-ascription presumably arose because somebody assumed without checking that, because their text shared a title with an example of Roud 568, it must be the same song. A beginner's mistake, so I expect that 'GEST' is right about farming the work out to students.

About a year ago I emailed them with the correct information. They never replied, but the entry was eventually corrected; so evidently they do pay attention when things are pointed out to them, even if it isn't immediately obvious.