Child was usually very generous with his comments but I think he somewhat eventually regretted his 'inclusive' policy. He must have been aware of how the ballad was considered in his time to have even offered such a comment.

I am in complete agreement with your view as you already know.

The fact that versions of the ballad were found in Scotland, Yorkshire, Cheshire and I think Hampshire in the 20th century have little bearing on where the ballad and its relatives came from in the 18th century. There are also big question marks over Lizie Wan and it's quite possible both were developments/adaptations from The Two Brothers.

'It appears to me that the most artistic and best-known version, first given to the world in Percy's Reliques, is a literary rehandling of the traditional song' Bronson.