Oh, no cringeing in this case!  As Anglo says, Doerflinger printed no tune (presumably he didn't have one?) so it's up for grabs.  What I try to do where possible is find a tune from a version collected in the same region, or failing that one with as close a text as possible, but it can't always be done.  Many published songs are set to tunes from elsewhere in any case, and even otherwise reputable collectors and editors don't always say so or identify their source, though it's a pity.  So long as it's on record where the words and tune both came from (and that the connection is a best-guess) then there's no need for anyone to be inadvertently misled.

As you know, what does worry me is people adding tunes from unspecified sources to texts that may have nothing to do with them at all, sometimes just because they have similar titles, but that isn't an issue here.  I can't help with Coasts of Peru at all, I'm afraid.