yes, well done, Daniel, for pulling this together.

Just a few points which you might find helpful.

Personal names/proper nouns, as you can see are notoriously fickle in ballad reproduction, oral tradition and print and manuscript. Names can be changed deliberately as well as by accident, for all sorts of reasons.
You rightly say Allan Tyne is very likely a mondegreen, but there are cases, fewer undoubtedly, where someone has taken an odd sounding name and altered it to a name more plausible.

You mention the Flying Highwayman. This is very likely the broadside ballad 'Young Morgan' which on some sheets uses that title. Unfortunately though I've got lots of copies I don't think any of them are on the Bodleian site for you to look at. There is a version in Holloway and Black Vol 1 at p103.

Also the 8 page publications printed on a single sheet are known as chapbooks (cheap books sold by chapmen on the streets and in rural areas).

There are plenty of Irish highwaymen ballads, mostly their exploits take place in England (richer pickings) Willie Brennan, Wild and Wicked Youth, Whiskey in the Jar, and others.

Keep up the good work.